diff --git a/css/main.css b/css/main.css
index 29e6d16b..6d8f52c3 100644
--- a/css/main.css
+++ b/css/main.css
@@ -29,7 +29,7 @@ div, span, a, ul, li, textarea, input, button {
     text-shadow: none !important;
 }
 
-.btn, .navbar-inner, .ui-layout-east, .ui-layout-south, textarea, input, .add-on {
+.btn, .navbar-inner, .ui-layout-east, .ui-layout-south, textarea, .add-on {
     border: none !important;
 }
 
@@ -38,10 +38,9 @@ div, span, a, ul, li, textarea, input, button {
     text-align: left;
 }
 
-.input-prepend input,
+input,
 .input-prepend .btn,
-.input-prepend .add-on
- {
+.input-prepend .add-on {
     border: 1px solid #ebebeb !important;
 }
 
diff --git a/index.html b/index.html
index 2b58c763..0a6b6045 100644
--- a/index.html
+++ b/index.html
@@ -5,8 +5,10 @@
 <link rel="icon" href="img/stackedit-32.ico" type="image/x-icon">
 <link rel="shortcut icon" href="img/stackedit-32.ico"
 	type="image/x-icon">
-<meta name="keywords" content="Markdown, Editor, PageDown, Stack Overflow, Stack Exchange">
-<meta name="description" content="StackEdit is a free, open-source Markdown editor based on PageDown, the Markdown library used by Stack Overflow and the other Stack Exchange sites.">
+<meta name="keywords"
+	content="Markdown, Editor, PageDown, Stack Overflow, Stack Exchange">
+<meta name="description"
+	content="StackEdit is a free, open-source Markdown editor based on PageDown, the Markdown library used by Stack Overflow and the other Stack Exchange sites.">
 <meta name="author" content="Benoit Schweblin">
 <meta name="viewport" content="width=device-width, initial-scale=1.0">
 <link href="css/main.css" rel="stylesheet" media="screen">
@@ -23,10 +25,10 @@
 				<li class="btn-group"><button class="btn action-force-sync"
 						title="Synchronize">
 						<i class="icon-refresh"></i>
-					</button><button class="btn action-publish"
-                        title="Publish">
-                        <i class="icon-share"></i>
-                    </button></li>
+					</button>
+					<button class="btn action-publish" title="Publish">
+						<i class="icon-share"></i>
+					</button></li>
 				<li class="btn-group"><button class="btn action-create-file"
 						title="New local document">
 						<i class="icon-file"></i>
@@ -70,22 +72,22 @@
 							data-target="#modal-manage-sync"><i class="icon-refresh"></i>
 								Manage synchronization</a></li>
 						<li class="divider"></li>
-                        <li class="dropdown-submenu"><a href="#"><i
-                                class="icon-share"></i> Publish</a>
-                            <ul class="dropdown-menu">
-                                <li><a href="#" class="action-publish-github"><i
-                                class="icon-github"></i> GitHub</a></li>
-                                <li><a href="#" class="action-publish-blogger"><i
-                                class="icon-blogger"></i> Blogger</a></li>
-                                <li><a href="#" class="action-publish-wordpress"><i
-                                class="icon-wordpress"></i> WordPress</a></li>
-                                <li><a href="#" class="action-publish-tumblr"><i
-                                class="icon-tumblr"></i> Tumblr</a></li>
-                            </ul></li>
-                        <li><a href="#" data-toggle="modal"
-                            data-target="#modal-manage-publication"><i class="icon-share"></i>
-                                Manage publication</a></li>
-                        <li class="divider"></li>
+						<li class="dropdown-submenu"><a href="#"><i
+								class="icon-share"></i> Publish on</a>
+							<ul class="dropdown-menu">
+								<li><a href="#" class="action-publish-github"><i
+										class="icon-github"></i> GitHub</a></li>
+								<li><a href="#" class="action-publish-blogger"><i
+										class="icon-blogger"></i> Blogger</a></li>
+								<li><a href="#" class="action-publish-wordpress"><i
+										class="icon-wordpress"></i> WordPress</a></li>
+								<li><a href="#" class="action-publish-tumblr"><i
+										class="icon-tumblr"></i> Tumblr</a></li>
+							</ul></li>
+						<li><a href="#" data-toggle="modal"
+							data-target="#modal-manage-publication"><i class="icon-share"></i>
+								Manage publication</a></li>
+						<li class="divider"></li>
 						<li><a href="#" data-toggle="modal"
 							data-target="#modal-settings" class="action-load-settings"><i
 								class="icon-cog"></i> Settings</a></li>
@@ -256,55 +258,47 @@
 		</div>
 	</div>
 
-    <div id="modal-publish-existing" class="modal hide">
-        <div class="modal-header">
-            <button type="button" class="close" data-dismiss="modal"
-                aria-hidden="true">&times;</button>
-            <h3>Publish</h3>
-        </div>
-        <div class="modal-body">
-            <dl class="dl-horizontal">
-                <dt>Would you like to:</dt>
-                <dd>
-                    <label class="radio"> <input type="radio"
-                        name="radio-publish-existing" value="new">
-                        Create a new Post
-                    </label> <label class="radio"> <input type="radio"
-                        name="radio-publish-existing" value="existing"> Edit an existing post
-                    </label>
-                </dd>
-            </dl>
-        </div>
-        <div class="modal-footer">
-            <a href="#" class="btn" data-dismiss="modal">Cancel</a> <a href="#"
-                data-dismiss="modal" class="btn btn-primary action-publish-next">Next</a>
-        </div>
-    </div>
-
-    <div id="modal-publish-format" class="modal hide">
-        <div class="modal-header">
-            <button type="button" class="close" data-dismiss="modal"
-                aria-hidden="true">&times;</button>
-            <h3>Publish</h3>
-        </div>
-        <div class="modal-body">
-            <dl class="dl-horizontal">
-                <dt>Publish as:</dt>
-                <dd>
-                    <label class="radio"> <input type="radio"
-                        name="radio-publish-format" value="markdown">
-                        Markdown format
-                    </label> <label class="radio"> <input type="radio"
-                        name="radio-publish-format" value="html"> HTML format
-                    </label>
-                </dd>
-            </dl>
-        </div>
-        <div class="modal-footer">
-            <a href="#" class="btn" data-dismiss="modal">Cancel</a> <a href="#"
-                data-dismiss="modal" class="btn btn-primary action-publish-finish">OK</a>
-        </div>
-    </div>
+	<div id="modal-publish" class="modal hide">
+		<div class="modal-header">
+			<button type="button" class="close" data-dismiss="modal"
+				aria-hidden="true">&times;</button>
+			<h3>Publish</h3>
+		</div>
+		<div class="modal-body">
+			<div class="form-horizontal">
+				<div class="control-group control-publish-blogger">
+					<label class="control-label" for="input-publish-blogger-url">Blog URL</label>
+					<div class="controls">
+						<input type="text" id="input-publish-blogger-url"
+							placeholder="http://exemple.blogger.com/">
+					</div>
+				</div>
+				<div class="control-group control-publish-blogger">
+					<label class="control-label" for="input-publish-blogger-postid">Update existing post ID (optional)</label>
+					<div class="controls">
+						<input type="text" id="input-publish-blogger-postid"
+							placeholder="Post ID">
+					</div>
+				</div>
+				<div class="control-group">
+					<div class="control-label">Publish as</div>
+					<div class="controls">
+						<label class="radio"> <input type="radio"
+							name="radio-publish-format" value="markdown"> Markdown
+							format
+						</label> <label class="radio"> <input type="radio"
+							name="radio-publish-format" value="html"> HTML format
+						</label>
+					</div>
+				</div>
+			</div>
+		</div>
+		<div class="modal-footer">
+			<a href="#" class="btn" data-dismiss="modal">Cancel</a>
+			<a href="#" data-dismiss="modal"
+				class="btn btn-primary action-publish-ok">OK</a>
+		</div>
+	</div>
 
 	<div id="modal-settings" class="modal hide">
 		<div class="modal-header">
@@ -313,17 +307,20 @@
 			<h3>Settings</h3>
 		</div>
 		<div class="modal-body">
-			<dl class="dl-horizontal">
-				<dt>Layout orientation:</dt>
-				<dd>
-					<label class="radio"> <input type="radio"
-						name="radio-layout-orientation" value="horizontal">
-						Horizontal
-					</label> <label class="radio"> <input type="radio"
-						name="radio-layout-orientation" value="vertical"> Vertical
-					</label>
-				</dd>
-			</dl>
+			<div class="form-horizontal">
+				<div class="control-group">
+					<div class="control-label">Layout orientation</div>
+					<div class="controls">
+						<label class="radio"> <input type="radio"
+							name="radio-layout-orientation" value="horizontal">
+							Horizontal
+						</label> <label class="radio"> <input type="radio"
+							name="radio-layout-orientation" value="vertical">
+							Vertical
+						</label>
+					</div>
+				</div>
+			</div>
 		</div>
 		<div class="modal-footer">
 			<a href="#" class="btn" data-dismiss="modal">Cancel</a> <a href="#"
@@ -376,7 +373,7 @@
 					<a target="_blank" href="http://twitter.github.com/bootstrap/">Bootstrap</a>
 				</dd>
 				<dd>
-					<a target="_blank" href="http://glyphicons.com/">GLYPHICONS</a>
+					<a target="_blank" href="http://glyphicons.com/">Glyphicons</a>
 				</dd>
 				<dd>
 					<a target="_blank" href="https://github.com/stanlemon/jGrowl/">jGrowl</a>
@@ -403,8 +400,24 @@
 		<div class="modal-footer">
 			<a href="#" class="btn btn-primary" data-dismiss="modal">Close</a>
 		</div>
-
 	</div>
+
+	<div id="modal-non-unique" class="modal hide">
+		<div class="modal-header">
+			<h3>Stopped...</h3>
+		</div>
+		<div class="modal-body">
+			<p>StackEdit has stopped because another instance was running on
+				the same browser.</p>
+			<p class="muted">If you want to reopen StackEdit, click on
+				"Reload".</p>
+		</div>
+		<div class="modal-footer">
+			<a href="javascript:window.location.reload();"
+				class="btn btn-primary">Reload</a>
+		</div>
+	</div>
+
 	<div id="dropboxjs" data-app-key="x0k2l8puemfvg0o"></div>
 </body>
 </html>
diff --git a/js/async-runner.js b/js/async-runner.js
index 1ce24a38..37bf1636 100644
--- a/js/async-runner.js
+++ b/js/async-runner.js
@@ -6,17 +6,20 @@
  *  - an optional onError() function
  *  - an optional timeout field (default is 30000)
  */
-define(["core"], function(core) {
+define(function() {
 	
 	var asyncTaskRunner = {};
 	
+	// Dependencies
+	var core = undefined;
+	
 	var asyncTaskQueue = [];
 	var currentTask = undefined;
 	var currentTaskRunning = false;
-	var currentTaskStartTime = core.currentTime;
+	var currentTaskStartTime = 0;
 	
 	// Run the next task in the queue if any and no other is running
-	asyncTaskRunner.runTask = function() {
+	function runTask() {
 		
 		// If there is a task currently running
 		if(currentTaskRunning === true) {
@@ -42,17 +45,6 @@ define(["core"], function(core) {
 			// Set task attributes and functions
 			currentTask.finished = false;
 			currentTask.retryCounter = 0;
-			currentTask.finish = function() {
-				this.finished = true;
-				currentTask = undefined;
-				currentTaskRunning = false;
-				if(asyncTaskQueue.length === 0) {
-					core.showWorkingIndicator(false);
-				}
-				else {
-					asyncTaskRunner.runTask();
-				}
-			};
 			currentTask.success = function() {
 				runSafe(this.onSuccess);
 			};
@@ -68,8 +60,7 @@ define(["core"], function(core) {
 					return;
 				}
 				// Implement an exponential backoff
-				var delay = (Math.pow(2, currentTask.retryCounter++) + Math.random()) * 1000;
-				console.log(delay);
+				var delay = Math.pow(2, currentTask.retryCounter++) * 1000;
 				currentTaskStartTime = core.currentTime + delay;
 				currentTaskRunning = false;
 				asyncTaskRunner.runTask();
@@ -81,6 +72,11 @@ define(["core"], function(core) {
 			currentTaskRunning = true;
 			currentTask.run();
 		}
+	}
+	
+	asyncTaskRunner.runTask = function() {		
+		// Use setTimeout to avoid stack overflow
+		setTimeout(runTask, 0);
 	};
 	
 	function runSafe(func) {
@@ -104,12 +100,16 @@ define(["core"], function(core) {
 		}
 	}
 	
-	// Add a task in the queue
+	// Add a task into the queue
 	asyncTaskRunner.addTask = function(asyncTask) {
 		asyncTaskQueue.push(asyncTask);
 		asyncTaskRunner.runTask();
 	};
 	
+	asyncTaskRunner.init = function(coreModule) {
+		core = coreModule;
+	};
+	
 	return asyncTaskRunner;
 });
 
diff --git a/js/config.js b/js/config.js
index 663c8229..732eb6ca 100644
--- a/js/config.js
+++ b/js/config.js
@@ -1,5 +1,6 @@
-var GOOGLE_SCOPES = [ 'https://www.googleapis.com/auth/drive.install',
-    'https://www.googleapis.com/auth/drive' ];
+var GOOGLE_SCOPES = [ "https://www.googleapis.com/auth/drive.install",
+	"https://www.googleapis.com/auth/drive",
+	"https://www.googleapis.com/auth/blogger" ];
 var GOOGLE_DRIVE_APP_ID = "241271498917";
 var DROPBOX_APP_KEY = "lq6mwopab8wskas";
 var DROPBOX_APP_SECRET = "851fgnucpezy84t";
@@ -10,13 +11,14 @@ var AJAX_TIMEOUT = 10000;
 var ASYNC_TASK_DEFAULT_TIMEOUT = 30000;
 var AUTH_POPUP_TIMEOUT = 90000;
 var SYNC_PERIOD = 180000;
+var USER_IDLE_THRESHOLD = 300000;
 var SYNC_PROVIDER_GDRIVE = "sync.gdrive.";
 var SYNC_PROVIDER_DROPBOX = "sync.dropbox.";
 
 // Use by Google's client.js
 var delayedFunction = undefined;
 function runDelayedFunction() {
-    if (delayedFunction !== undefined) {
-        delayedFunction();
-    }
+	if (delayedFunction !== undefined) {
+		delayedFunction();
+	}
 }
diff --git a/js/core.js b/js/core.js
index 005e8786..be9261f2 100644
--- a/js/core.js
+++ b/js/core.js
@@ -1,16 +1,58 @@
-define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function($) {
+define(
+	[ "jquery", "file-manager", "google-helper", "dropbox-helper",
+		"synchronizer", "publisher", "async-runner", "bootstrap", "jgrowl",
+		"layout", "Markdown.Editor", "config", "custo" ],
+	function($, fileManager, googleHelper, dropboxHelper, synchronizer,
+		publisher, asyncTaskRunner) {
 	
 	var core = {};
 	
-	// Time shared by others modules
-	core.currentTime = new Date().getTime();
-	core.updateCurrentTime = function() {
-		core.currentTime = new Date().getTime();
-	};
-	
 	// Usage: callback = callback || core.doNothing;
 	core.doNothing = function() {};
 	
+	// Time shared by others modules
+	core.currentTime = new Date().getTime();
+	function updateCurrentTime() {
+		core.currentTime = new Date().getTime();
+	}
+	
+	// Used to detect user activity
+	var userReal = false;
+	var userActive = false;
+	var windowUnique = true;
+	var userLastActivity = 0;
+	function setUserActive() {
+		userReal = true;
+		userActive = true;
+		userLastActivity = core.currentTime;
+	};
+	function isUserActive() {
+		if(userActive === true 
+			&& core.currentTime - userLastActivity > USER_IDLE_THRESHOLD) {
+			userActive = false;
+		}
+		return userActive && windowUnique;
+	}
+	
+	// Used to only have 1 window of the application in the same browser
+	var windowId = undefined;
+	core.checkWindowUnique = function() {
+		if(userReal === false || windowUnique === false) {
+			return;
+		}
+		if(windowId === undefined) {
+			windowId = Math.random().toString(36);
+			localStorage["frontWindowId"] = windowId;
+		}
+		var frontWindowId = localStorage["frontWindowId"];
+		if(frontWindowId != windowId) {
+			windowUnique = false;
+			$('#modal-non-unique').modal({
+				backdrop: "static",
+				keyboard: false
+			});
+		}
+	};
 
 	// Useful function
 	core.getInputValue = function(element, event) {
@@ -58,10 +100,6 @@ define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function(
 	var offlineTime = core.currentTime;
 	var offlineListeners = [];
 	
-	core.addOfflineListener = function(listener) {
-		offlineListeners.push(listener);
-	};
-	
 	core.setOffline = function() {
 		offlineTime = core.currentTime;
 		if(core.isOffline === false) {
@@ -89,7 +127,7 @@ define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function(
 		}
 	};
 
-	core.checkOnline = function() {
+	function checkOnline() {
 		// Try to reconnect if we are offline but we have some network
 		if (core.isOffline === true && navigator.onLine === true
 			&& offlineTime + CHECK_ONLINE_PERIOD < core.currentTime) {
@@ -102,7 +140,7 @@ define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function(
 				core.setOnline();
 			});
 		}
-	};
+	}
 	
 	// Setting management
 	var settings = { layoutOrientation : "horizontal" };
@@ -338,10 +376,10 @@ define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function(
 	
 	// Used to setup an empty localStorage 
 	function setupLocalStorage() {
-		if (localStorage["file.counter"] === undefined 
-			|| localStorage["file.list"] === undefined) {
+		if (localStorage["file.counter"] === undefined) {
 			localStorage["file.counter"] = "0";
 			localStorage["file.list"] = ";";
+			localStorage["version"] = "v1";
 		}		
 	}
 
@@ -351,19 +389,22 @@ define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function(
 		
 		// from v0 to v1
 		if(version === undefined) {
+			
+			// Synchronization queue not used anymore
+			localStorage.removeItem("sync.queue");
+			localStorage.removeItem("sync.current");
+			
 			var fileIndexList = localStorage["file.list"].split(";");
 			for ( var i = 1; i < fileIndexList.length - 1; i++) {
 				var fileIndex = fileIndexList[i];
 				localStorage[fileIndex + ".publish"] = ";";
-				var titleCRC = core.crc32(localStorage[fileIndex + ".title"]);
-				var contentCRC = core.crc32(localStorage[fileIndex + ".content"]);
 				var fileSyncIndexList = localStorage[fileIndex + ".sync"].split(";");
 				for ( var j = 1; j < fileSyncIndexList.length - 1; j++) {
 					var fileSyncIndex = fileSyncIndexList[j];
-					localStorage[fileSyncIndex + ".contentCRC"] = contentCRC;
+					localStorage[fileSyncIndex + ".contentCRC"] = "0";
 					// We store title CRC only for Google Drive synchronization
 					if(localStorage[fileSyncIndex + ".etag"] !== undefined) {
-						localStorage[fileSyncIndex + ".titleCRC"] = titleCRC;
+						localStorage[fileSyncIndex + ".titleCRC"] = "0";
 					}
 				}
 			}
@@ -389,6 +430,9 @@ define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function(
 			core.setOffline();
 		}
 		
+		// Detect user activity
+		$(document).mousemove(setUserActive).keypress(setUserActive);
+		
 		// Avoid dropdown to close when clicking on submenu
 		$('.dropdown-submenu > a').click(function(e) {
 			e.stopPropagation();
@@ -421,8 +465,37 @@ define(["jquery", "bootstrap", "jgrowl", "layout", "Markdown.Editor"], function(
 
 		$(".action-apply-settings").click(function() {
 			core.saveSettings();
-			location.reload();
+			window.location.reload();
 		});
+		
+		// Init asyncTaskRunner
+		asyncTaskRunner.init(core);
+		
+		// Init helpers
+		googleHelper.init(core, fileManager);
+		dropboxHelper.init(core, fileManager);
+		
+		// Init publisher
+		publisher.init(core, fileManager);
+		
+		// Init synchronizer
+		synchronizer.init(core, fileManager);
+		offlineListeners.push(synchronizer.updateSyncButton);		
+		
+		// Init file manager
+		fileManager.init(core);
+		
+		// Do periodic tasks
+		window.setInterval(function() {
+			updateCurrentTime();
+			core.checkWindowUnique();
+			if(isUserActive() === false) {
+				return;
+			}
+			synchronizer.sync();
+			asyncTaskRunner.runTask();
+			checkOnline();
+		}, 1000);
 	};
 
 	return core;
diff --git a/js/dropbox-helper.js b/js/dropbox-helper.js
index b31baabd..bc2c522e 100644
--- a/js/dropbox-helper.js
+++ b/js/dropbox-helper.js
@@ -1,6 +1,7 @@
-define(["jquery", "core", "async-runner"], function($, core, asyncTaskRunner) {
+define(["jquery", "async-runner"], function($, asyncTaskRunner) {
 
 	// Dependencies
+	var core = undefined;
 	var fileManager = undefined;
 
 	var client = undefined;
@@ -372,7 +373,8 @@ define(["jquery", "core", "async-runner"], function($, core, asyncTaskRunner) {
 		});
 	};
 
-	dropboxHelper.init = function(fileManagerModule) {
+	dropboxHelper.init = function(coreModule, fileManagerModule) {
+		core = coreModule;
 		fileManager = fileManagerModule;
 	};
 	
diff --git a/js/file-manager.js b/js/file-manager.js
index 3cca4d6e..4fe9307c 100644
--- a/js/file-manager.js
+++ b/js/file-manager.js
@@ -1,115 +1,11 @@
-define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "publisher", "async-runner"],
-	function($, core, googleHelper, dropboxHelper, synchronizer, publisher, asyncTaskRunner) {
+define(["jquery", "google-helper", "dropbox-helper", "synchronizer", "publisher"],
+	function($, googleHelper, dropboxHelper, synchronizer, publisher) {
 
 	var fileManager = {};
 
-	fileManager.init = function() {
-		googleHelper.init(fileManager);
-		dropboxHelper.init(fileManager);
-		publisher.init(fileManager);
-		
-		var changeSyncButtonState = function() {
-			if(synchronizer.isRunning() || synchronizer.isQueueEmpty() || core.isOffline) {
-				$(".action-force-sync").addClass("disabled");
-			}
-			else {
-				$(".action-force-sync").removeClass("disabled");
-			}
-		};
-		core.addOfflineListener(changeSyncButtonState);
-		synchronizer.init(fileManager, {
-			onSyncBegin : changeSyncButtonState,
-			onSyncEnd : changeSyncButtonState,
-			onQueueChanged : changeSyncButtonState
-		});
-		$(".action-force-sync").click(function() {
-			if(!$(this).hasClass("disabled")) {
-				synchronizer.forceSync();
-			}
-		});
-		
-		fileManager.selectFile();
-
-		// Do periodic tasks
-		window.setInterval(function() {
-			core.updateCurrentTime();
-			synchronizer.sync();
-			asyncTaskRunner.runTask();
-			core.checkOnline();
-		}, 1000);
-
-		$(".action-create-file").click(function() {
-			var fileIndex = fileManager.createFile();
-			fileManager.selectFile(fileIndex);
-			$("#file-title").click();
-		});
-		$(".action-remove-file").click(function() {
-			fileManager.deleteFile();
-			fileManager.selectFile();
-		});
-		$("#file-title").click(function() {
-			$(this).hide();
-			$("#file-title-input").show().focus();
-		});
-		$("#file-title-input").blur(function() {
-			var title = $.trim($(this).val());
-			if (title) {
-				var fileIndexTitle = localStorage["file.current"] + ".title";
-				if (title != localStorage[fileIndexTitle]) {
-					localStorage[fileIndexTitle] = title;
-					fileManager.updateFileTitles();
-					fileManager.saveFile();
-				}
-			}
-			$(this).hide();
-			$("#file-title").show();
-		});
-		$(".action-download-md").click(
-			function() {
-				var content = $("#wmd-input").val();
-				var uriContent = "data:application/octet-stream;base64,"
-					+ core.encodeBase64(content);
-				window.open(uriContent, 'file');
-			});
-		$(".action-download-html").click(
-			function() {
-				var content = $("#wmd-preview").html();
-				var uriContent = "data:application/octet-stream;base64,"
-					+ core.encodeBase64(content);
-				window.open(uriContent, 'file');
-			});
-		$(".action-upload-gdrive-root").click(function() {
-			uploadGdrive();
-		});
-		$(".action-upload-gdrive-select").click(function() {
-			// This action is not available because picker does not support
-			// folder selection yet
-			googleHelper.picker(function(ids) {
-				if(ids !== undefined && ids.length !== 0) {
-					uploadGdrive(undefined, ids[0]);
-				}
-			}, true);
-		});
-		$(".action-download-gdrive").click(function() {
-			googleHelper.picker(importGdrive);
-		});
-		$(".action-manual-gdrive").click(function(event) {
-			var fileId = core.getInputValue($("#manual-gdrive-fileid"), event);
-			manualGdrive(fileId);
-		});
-		$(".action-download-dropbox").click(function() {
-			dropboxHelper.picker(importDropbox);
-		});
-		$(".action-upload-dropbox").click(function(event) {
-			var path = core.getInputValue($("#upload-dropbox-path"), event);
-			manualDropbox(path);
-		});
-		$(".action-manual-dropbox").click(function(event) {
-			var path = core.getInputValue($("#manual-dropbox-path"), event);
-			manualDropbox(path);
-		});
-	};
-
+	// Dependencies
+	var core = undefined;
+	
 	// Caution: this function recreate the editor (reset undo operations)
 	var fileDescList = [];
 	fileManager.selectFile = function(fileIndex) {
@@ -118,8 +14,9 @@ define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "pu
 			fileIndex = this.createFile();
 		}
 		
-		fileIndex = fileIndex || localStorage["file.current"];
 		if(fileIndex !== undefined) {
+			// Since we are going to modify current file
+			core.checkWindowUnique();
 			localStorage["file.current"] = fileIndex;
 		}
 
@@ -128,7 +25,7 @@ define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "pu
 		refreshManageSync();
 		
 		// Recreate the editor
-		var fileIndex = localStorage["file.current"];
+		fileIndex = localStorage["file.current"];
 		$("#wmd-input").val(localStorage[fileIndex + ".content"]);
 		core.createEditor(function() {
 			fileManager.saveFile();
@@ -174,6 +71,8 @@ define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "pu
 		var fileIndexCurrent = localStorage["file.current"];
 		fileIndex = fileIndex || fileIndexCurrent;
 		if(fileIndex == fileIndexCurrent) {
+			// Since we are going to modify current file
+			core.checkWindowUnique();
 			localStorage.removeItem("file.current");
 		}
 
@@ -195,7 +94,7 @@ define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "pu
 		var content = $("#wmd-input").val();
 		var fileIndex = localStorage["file.current"];
 		localStorage[fileIndex + ".content"] = content;
-		synchronizer.addFileForUpload(fileIndex);
+		synchronizer.notifyChange(fileIndex);
 	};
 	
 	fileManager.updateFileTitles = function() {
@@ -218,6 +117,8 @@ define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "pu
 		var fileIndex = localStorage["file.current"];
 		// If no default file take first one
 		if (!fileIndex) {
+			// Since we are going to modify current file
+			core.checkWindowUnique();
 			fileIndex = fileDescList[0].index;
 			localStorage["file.current"] = fileIndex;
 		}
@@ -256,6 +157,8 @@ define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "pu
 			} else {
 				a.prop("href", "#").click((function(fileIndex) {
 					return function() {
+						// Since we are going to modify current file
+						core.checkWindowUnique();
 						localStorage["file.current"] = fileIndex;
 						fileManager.selectFile();
 					};
@@ -445,5 +348,82 @@ define(["jquery", "core", "google-helper", "dropbox-helper", "synchronizer", "pu
 		}
 	}
 
+	fileManager.init = function(coreModule) {
+		core = coreModule;
+		
+		fileManager.selectFile();
+
+		$(".action-create-file").click(function() {
+			var fileIndex = fileManager.createFile();
+			fileManager.selectFile(fileIndex);
+			$("#file-title").click();
+		});
+		$(".action-remove-file").click(function() {
+			fileManager.deleteFile();
+			fileManager.selectFile();
+		});
+		$("#file-title").click(function() {
+			$(this).hide();
+			$("#file-title-input").show().focus();
+		});
+		$("#file-title-input").blur(function() {
+			var title = $.trim($(this).val());
+			if (title) {
+				var fileIndexTitle = localStorage["file.current"] + ".title";
+				if (title != localStorage[fileIndexTitle]) {
+					localStorage[fileIndexTitle] = title;
+					fileManager.updateFileTitles();
+					fileManager.saveFile();
+				}
+			}
+			$(this).hide();
+			$("#file-title").show();
+		});
+		$(".action-download-md").click(
+			function() {
+				var content = $("#wmd-input").val();
+				var uriContent = "data:application/octet-stream;base64,"
+					+ core.encodeBase64(content);
+				window.open(uriContent, 'file');
+			});
+		$(".action-download-html").click(
+			function() {
+				var content = $("#wmd-preview").html();
+				var uriContent = "data:application/octet-stream;base64,"
+					+ core.encodeBase64(content);
+				window.open(uriContent, 'file');
+			});
+		$(".action-upload-gdrive-root").click(function() {
+			uploadGdrive();
+		});
+		$(".action-upload-gdrive-select").click(function() {
+			// This action is not available because picker does not support
+			// folder selection
+			googleHelper.picker(function(ids) {
+				if(ids !== undefined && ids.length !== 0) {
+					uploadGdrive(undefined, ids[0]);
+				}
+			}, true);
+		});
+		$(".action-download-gdrive").click(function() {
+			googleHelper.picker(importGdrive);
+		});
+		$(".action-manual-gdrive").click(function(event) {
+			var fileId = core.getInputValue($("#manual-gdrive-fileid"), event);
+			manualGdrive(fileId);
+		});
+		$(".action-download-dropbox").click(function() {
+			dropboxHelper.picker(importDropbox);
+		});
+		$(".action-upload-dropbox").click(function(event) {
+			var path = core.getInputValue($("#upload-dropbox-path"), event);
+			manualDropbox(path);
+		});
+		$(".action-manual-dropbox").click(function(event) {
+			var path = core.getInputValue($("#manual-dropbox-path"), event);
+			manualDropbox(path);
+		});
+	};
+
 	return fileManager;
 });
diff --git a/js/google-helper.js b/js/google-helper.js
index 6960ec60..3c099a12 100644
--- a/js/google-helper.js
+++ b/js/google-helper.js
@@ -1,6 +1,7 @@
-define(["jquery", "core", "async-runner"], function($, core, asyncTaskRunner) {
+define(["jquery", "async-runner"], function($, asyncTaskRunner) {
 
 	// Dependencies
+	var core = undefined;
 	var fileManager = undefined;
 
 	var connected = false;
@@ -464,7 +465,8 @@ define(["jquery", "core", "async-runner"], function($, core, asyncTaskRunner) {
 		});
 	};
 
-	googleHelper.init = function(fileManagerModule) {
+	googleHelper.init = function(coreModule, fileManagerModule) {
+		core = coreModule;
 		fileManager = fileManagerModule;
 		var state = localStorage["sync.gdrive.state"];
 		if(state === undefined) {
diff --git a/js/main.js b/js/main.js
index 6611ead1..82f62fea 100644
--- a/js/main.js
+++ b/js/main.js
@@ -18,10 +18,10 @@ requirejs.config({
     }
 });
 
-require(["jquery", "core", "file-manager", "config", "custo"], function($, core, fileManager) {
+require(["jquery", "core"], function($, core) {
 	$(function() {
 		
-		// If browser detected a new application cache.
+		// If browser has detected a new application cache.
 	    if (window.applicationCache
 				&& window.applicationCache.status === window.applicationCache.UPDATEREADY) {
 			window.applicationCache.swapCache();
@@ -30,6 +30,5 @@ require(["jquery", "core", "file-manager", "config", "custo"], function($, core,
 		}
 	    
 		core.init();
-		fileManager.init();
 	});
 });
diff --git a/js/publisher.js b/js/publisher.js
index 2249e4dc..f246aa06 100644
--- a/js/publisher.js
+++ b/js/publisher.js
@@ -1,37 +1,44 @@
-define(["jquery", "core", "async-runner"], function($, core, asyncTaskRunner) {
+define(["jquery"], function($) {
 	
 	// Dependencies
+	var core = undefined;
 	var fileManager = undefined;
 
 	var publisher = {};
 	
 	var wizardProvider = undefined;
 	
-	function initWizard(provider) {
+	function initWizard(provider, defaultPublishFormat) {
+		defaultPublishFormat = defaultPublishFormat || "markdown";
 		wizardProvider = provider;
-		$("input:radio[name=radio-publish-existing][value=new]").prop("checked", true);
-		$("input:radio[name=radio-publish-format][value=markdown]").prop("checked", true);
+		
+		// Show/hide controls depending on provider
+		$('div[class*=" control-publish-"]').hide().filter(".control-publish-" + provider).show();
+		
+		// Reset fields
+		$("#modal-publish input[type=text]").val("");
+		$("input:radio[name=radio-publish-format][value=" + defaultPublishFormat + "]").prop("checked", true);
+		
+		// Open dialog box
+		$("#modal-publish").modal();
 	}
 	
-	publisher.init = function(fileManagerModule) {
+	publisher.init = function(coreModule, fileManagerModule) {
+		core = coreModule;
 		fileManager = fileManagerModule;
-		$("#action-publish-github").click(function() {
+		$(".action-publish-github").click(function() {
 			initWizard("github");
 		});
-		$("#action-publish-blogger").click(function() {
-			initWizard("blogger");
+		$(".action-publish-blogger").click(function() {
+			initWizard("blogger", "html");
 		});
-		$("#action-publish-wordpress").click(function() {
+		$(".action-publish-wordpress").click(function() {
 			initWizard("wordpress");
 		});
-		$("#action-publish-tumblr").click(function() {
+		$(".action-publish-tumblr").click(function() {
 			initWizard("tumblr");
 		});
 	};
 	
-	publisher.initWizard = function() {
-		
-	};
-	
 	return publisher;
 });
\ No newline at end of file
diff --git a/js/synchronizer.js b/js/synchronizer.js
index 7538fd39..fbaeb9ed 100644
--- a/js/synchronizer.js
+++ b/js/synchronizer.js
@@ -1,132 +1,141 @@
-define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core, googleHelper, dropboxHelper) {
+define(["jquery", "google-helper", "dropbox-helper"], function($, googleHelper, dropboxHelper) {
 	var synchronizer = {};
 	
 	// Dependencies
+	var core = undefined;
 	var fileManager = undefined;
 
 	// Used to know the providers we are connected to 
 	synchronizer.useGoogleDrive = false;
 	synchronizer.useDropbox = false;
 	
-	var onSyncBegin = undefined;
-	var onSyncEnd = undefined;
-	var onQueueChanged = undefined;
-
-	// A synchronization queue containing fileIndex that has to be synchronized
-	var syncUpQueue = undefined;
+	// Used to know if user can force synchronization
+	var uploadPending = false;
 	
-	synchronizer.init = function(fileManagerModule, options) {
-		fileManager = fileManagerModule;
-		onSyncBegin = options.onSyncBegin || core.doNothing;
-		onSyncEnd = options.onSyncEnd || core.doNothing;
-		onQueueChanged = options.onQueueChanged || core.doNothing;
-		
-		syncUpQueue = ";";
-		// Load the queue from localStorage in case a previous synchronization
-		// was aborted
-		if (localStorage["sync.queue"]) {
-			syncUpQueue = localStorage["sync.queue"];
-			onQueueChanged();
-		}
-		if (localStorage["sync.current"]) {
-			this.addFileForUpload(localStorage["sync.current"]);
-		}
-	};
-
 	// Add a file to the synchronization queue
-	synchronizer.addFileForUpload = function(fileIndex) {
+	synchronizer.notifyChange = function(fileIndex) {
 		// Check that file has synchronized locations
 		if(localStorage[fileIndex + ".sync"].length === 1) {
 			return;
 		}
-		// Check that file is not in the queue
-		if (syncUpQueue.indexOf(";" + fileIndex + ";") !== -1) {
-			return;
-		}
-		syncUpQueue += fileIndex + ";";
-		localStorage["sync.queue"] = syncUpQueue;
-		onQueueChanged();
+		uploadPending = true;
+		synchronizer.updateSyncButton();
 	};
 
 	// Recursive function to upload a single file on multiple locations
-	function fileUp(fileSyncIndexList, content, contentCRC, title, titleCRC, callback) {
-		if (fileSyncIndexList.length === 0) {
-			localStorage.removeItem("sync.current");
-			// run the next file synchronization
-			syncUp(callback);
+	var uploadFileSyncIndexList = [];
+	var uploadContent = undefined;
+	var uploadContentCRC = undefined;
+	var uploadTitle = undefined;
+	var uploadTitleCRC = undefined;
+	function locationUp(callback) {
+		
+		// No more synchronized location for this document
+		if (uploadFileSyncIndexList.length === 0) {
+			fileUp(callback);
+			return;
+		}
+		
+		// Dequeue a synchronized location
+		var fileSyncIndex = uploadFileSyncIndexList.pop();
+		if(!fileSyncIndex) {
+			locationUp(callback);
 			return;
 		}
-		var fileSyncIndex = fileSyncIndexList.pop();
 
 		// Skip if CRC has not changed
 		var syncContentCRC = localStorage[fileSyncIndex + ".contentCRC"];
 		var syncTitleCRC = localStorage[fileSyncIndex + ".titleCRC"];
-		if(contentCRC == syncContentCRC && (syncTitleCRC === undefined || titleCRC == syncTitleCRC)) {
-			fileUp(fileSyncIndexList, content, contentCRC, title, titleCRC, callback);
+		if(uploadContentCRC == syncContentCRC && (syncTitleCRC === undefined || uploadTitleCRC == syncTitleCRC)) {
+			locationUp(callback);
 			return;
 		}
+		
+		// If upload is going to run, go for an other upload cycle at the end
+		uploadCycle = true;
+		// When page is refreshed, this flag is false but should be true here
+		uploadPending = true;
 
 		// Try to find the provider
 		if (fileSyncIndex.indexOf(SYNC_PROVIDER_GDRIVE) === 0) {
 			var id = fileSyncIndex.substring(SYNC_PROVIDER_GDRIVE.length);
-			googleHelper.upload(id, undefined, title, content, function(result) {
+			googleHelper.upload(id, undefined, uploadTitle, uploadContent, function(result) {
 				if (result !== undefined) {
-					localStorage[fileSyncIndex + ".contentCRC"] = contentCRC;
-					localStorage[fileSyncIndex + ".titleCRC"] = titleCRC;
-					fileUp(fileSyncIndexList, content, contentCRC, title, titleCRC, callback);
+					localStorage[fileSyncIndex + ".contentCRC"] = uploadContentCRC;
+					localStorage[fileSyncIndex + ".titleCRC"] = uploadTitleCRC;
+					locationUp(callback);
 					return;
 				}
-				// If error we put the fileIndex back in the queue
-				synchronizer.addFileForUpload(localStorage["sync.current"]);
-				localStorage.removeItem("sync.current");
-				callback();
+				
+				// If error we abort the synchronization (retry later)
+				callback("abort");
 				return;
 			});
 		} else if (fileSyncIndex.indexOf(SYNC_PROVIDER_DROPBOX) === 0) {
 			var path = fileSyncIndex.substring(SYNC_PROVIDER_DROPBOX.length);
 			path = decodeURIComponent(path);
-			dropboxHelper.upload(path, content, function(result) {
+			dropboxHelper.upload(path, uploadContent, function(result) {
 				if (result !== undefined) {
-					localStorage[fileSyncIndex + ".contentCRC"] = contentCRC;
-					fileUp(fileSyncIndexList, content, contentCRC, title, titleCRC, callback);
+					localStorage[fileSyncIndex + ".contentCRC"] = uploadContentCRC;
+					locationUp(callback);
 					return;
 				}
-				// If error we put the fileIndex back in the queue
-				synchronizer.addFileForUpload(localStorage["sync.current"]);
-				localStorage.removeItem("sync.current");
-				callback();
+				
+				// If error we abort the synchronization (retry later)
+				callback("abort");
 				return;
 			});
 		} else {
-			fileUp(fileSyncIndexList, content, contentCRC, title, titleCRC, callback);
+			// This should never happen
+			console.error("Invalid fileSyncIndex: " + fileSyncIndex);
+			callback("error");
 		}
 	}
 
-	function syncUp(callback) {
-		// If nothing to synchronize
-		if (syncUpQueue.length === 1) {
-			callback();
+	// Recursive function to upload multiple files
+	var uploadFileIndexList = [];
+	function fileUp(callback) {
+		
+		// No more fileIndex to synchronize
+		if (uploadFileIndexList.length === 0) {
+			syncUp(callback);
+			return;
+		}
+		
+		// Dequeue a fileIndex
+		var fileIndex = uploadFileIndexList.pop();
+		var fileSyncIndexes = localStorage[fileIndex + ".sync"];
+		if(!fileIndex || fileSyncIndexes.length === 1) {
+			fileUp(callback);
 			return;
 		}
 
-		// Dequeue the fileIndex
-		var separatorPos = syncUpQueue.indexOf(";", 1);
-		var fileIndex = syncUpQueue.substring(1, separatorPos);
-		localStorage["sync.current"] = fileIndex;
-		syncUpQueue = syncUpQueue.substring(separatorPos);
-		localStorage["sync.queue"] = syncUpQueue;
-		onQueueChanged();
+		// Get document title/content 
+		uploadContent = localStorage[fileIndex + ".content"];
+		uploadContentCRC = core.crc32(uploadContent);
+		uploadTitle = localStorage[fileIndex + ".title"];
+		uploadTitleCRC = core.crc32(uploadTitle);
 
-		var content = localStorage[fileIndex + ".content"];
-		var title = localStorage[fileIndex + ".title"];
-		var contentCRC = core.crc32(content);
-		var titleCRC = core.crc32(title);
+		// Parse the list of synchronized locations associated to the document
+		uploadFileSyncIndexList = fileSyncIndexes.split(";");
+		locationUp(callback);
+	}
 
-		// Parse the list of synchronized locations associated to the file
-		var fileSyncIndexList = localStorage[fileIndex + ".sync"].split(";");
-		fileUp(fileSyncIndexList, content, contentCRC, title, titleCRC, callback);
-	};
+	// Used to upload document changes from local storage
+	var uploadCycle = false;
+	function syncUp(callback) {
+		if(uploadCycle === true) {
+			// New upload cycle
+			uploadCycle = false;
+			uploadFileIndexList = localStorage["file.list"].split(";");
+			fileUp(callback);
+		}
+		else {
+			callback();
+		} 
+	}
 
+	// Used to download file changes from Google Drive
 	function syncDownGdrive(callback) {
 		if (synchronizer.useGoogleDrive === false) {
 			callback();
@@ -136,12 +145,12 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 			+ "lastChangeId"]);
 		googleHelper.checkUpdates(lastChangeId, function(changes, newChangeId) {
 			if (changes === undefined) {
-				callback();
+				callback("error");
 				return;
 			}
 			googleHelper.downloadContent(changes, function(changes) {
 				if (changes === undefined) {
-					callback();
+					callback("error");
 					return;
 				}
 				var updateFileTitles = false;
@@ -155,32 +164,35 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 						localStorage.removeItem(fileSyncIndex + ".etag");
 						continue;
 					}
-					var title = localStorage[fileIndex + ".title"];
+					var localTitle = localStorage[fileIndex + ".title"];
 					// File deleted
 					if (change.deleted === true) {
 						fileManager.removeSync(fileSyncIndex);
 						updateFileTitles = true;
-						core.showMessage('"' + title + '" has been removed from Google Drive.');
+						core.showMessage('"' + localTitle + '" has been removed from Google Drive.');
 						continue;
 					}
-					var content = localStorage[fileIndex + ".content"];
+					var localTitleChanged = localStorage[fileSyncIndex + ".titleCRC"] == core.crc32(localTitle);
+					var localContent = localStorage[fileIndex + ".content"];
+					var localContentChanged = localStorage[fileSyncIndex + ".contentCRC"] == core.crc32(localContent);
 					var file = change.file;
-					var titleChanged = title != file.title;
-					var contentChanged = content != file.content;
-					// If file is in the upload queue we have a conflict
-					if ((titleChanged || contentChanged) && syncUpQueue.indexOf(";" + fileIndex + ";") !== -1) {
-						fileManager.createFile(title + " (backup)", content);
+					var fileTitleChanged = localTitle != file.title;
+					var fileContentChanged = localContent != file.content;
+					// Conflict detection
+					if ((fileTitleChanged === true && localTitleChanged === true)
+						|| (fileContentChanged === true && localContentChanged === true)) {
+						fileManager.createFile(localTitle + " (backup)", localContent);
 						updateFileTitles = true;
-						core.showMessage('Conflict detected on "' + title + '". A backup has been created locally.');
+						core.showMessage('Conflict detected on "' + localTitle + '". A backup has been created locally.');
 					}
 					// If file title changed
-					if(titleChanged) {
+					if(fileTitleChanged) {
 						localStorage[fileIndex + ".title"] = file.title;
 						updateFileTitles = true;
-						core.showMessage('"' + title + '" has been renamed to "' + file.title + '" on Google Drive.');
+						core.showMessage('"' + localTitle + '" has been renamed to "' + file.title + '" on Google Drive.');
 					}
 					// If file content changed
-					if(contentChanged) {
+					if(fileContentChanged) {
 						localStorage[fileIndex + ".content"] = file.content;
 						core.showMessage('"' + file.title + '" has been updated from Google Drive.');
 						if(fileIndex == localStorage["file.current"]) {
@@ -190,13 +202,11 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 					}
 					// Update file etag and CRCs
 					localStorage[fileSyncIndex + ".etag"] = file.etag;
-					var contentCRC = core.crc32(file.content);
-					localStorage[fileSyncIndex + ".contentCRC"] = contentCRC;
-					var titleCRC = core.crc32(file.title);
-					localStorage[fileSyncIndex + ".titleCRC"] = titleCRC;
+					localStorage[fileSyncIndex + ".contentCRC"] = core.crc32(file.content);
+					localStorage[fileSyncIndex + ".titleCRC"] = core.crc32(file.title);
 
 					// Synchronize file with others locations
-					synchronizer.addFileForUpload(fileIndex);
+					uploadPending = true;
 				}
 				if(updateFileTitles) {
 					fileManager.updateFileTitles();
@@ -208,6 +218,7 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 		});
 	}
 
+	// Used to download file changes from Dropbox
 	function syncDownDropbox(callback) {
 		if (synchronizer.useDropbox === false) {
 			callback();
@@ -216,12 +227,12 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 		var lastChangeId = localStorage[SYNC_PROVIDER_DROPBOX + "lastChangeId"];
 		dropboxHelper.checkUpdates(lastChangeId, function(changes, newChangeId) {
 			if (changes === undefined) {
-				callback();
+				callback("error");
 				return;
 			}
 			dropboxHelper.downloadContent(changes, function(changes) {
 				if (changes === undefined) {
-					callback();
+					callback("error");
 					return;
 				}
 				var updateFileTitles = false;
@@ -235,27 +246,28 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 						localStorage.removeItem(fileSyncIndex + ".version");
 						continue;
 					}
-					var title = localStorage[fileIndex + ".title"];
+					var localTitle = localStorage[fileIndex + ".title"];
 					// File deleted
 					if (change.wasRemoved === true) {
 						fileManager.removeSync(fileSyncIndex);
 						updateFileTitles = true;
-						core.showMessage('"' + title + '" has been removed from Dropbox.');
+						core.showMessage('"' + localTitle + '" has been removed from Dropbox.');
 						continue;
 					}
-					var content = localStorage[fileIndex + ".content"];
+					var localContent = localStorage[fileIndex + ".content"];
+					var localContentChanged = localStorage[fileSyncIndex + ".contentCRC"] == core.crc32(localContent);
 					var file = change.stat;
-					var contentChanged = content != file.content;
-					// If file is in the upload queue we have a conflict
-					if (contentChanged && syncUpQueue.indexOf(";" + fileIndex + ";") !== -1) {
-						fileManager.createFile(title + " (backup)", content);
+					var fileContentChanged = localContent != file.content;
+					// Conflict detection
+					if (fileContentChanged === true && localContentChanged === true) {
+						fileManager.createFile(localTitle + " (backup)", localContent);
 						updateFileTitles = true;
-						core.showMessage('Conflict detected on "' + title + '". A backup has been created locally.');
+						core.showMessage('Conflict detected on "' + localTitle + '". A backup has been created locally.');
 					}
 					// If file content changed
-					if(contentChanged) {
+					if(fileContentChanged) {
 						localStorage[fileIndex + ".content"] = file.content;
-						core.showMessage('"' + title + '" has been updated from Dropbox.');
+						core.showMessage('"' + localTitle + '" has been updated from Dropbox.');
 						if(fileIndex == localStorage["file.current"]) {
 							updateFileTitles = false; // Done by next function
 							fileManager.selectFile(); // Refresh editor
@@ -263,11 +275,10 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 					}
 					// Update file version and CRC
 					localStorage[fileSyncIndex + ".version"] = file.versionTag;
-					var contentCRC = core.crc32(file.content);
-					localStorage[fileSyncIndex + ".contentCRC"] = contentCRC;
+					localStorage[fileSyncIndex + ".contentCRC"] = core.crc32(file.content);
 					
 					// Synchronize file with others locations
-					synchronizer.addFileForUpload(fileIndex);
+					uploadPending = true;
 				}
 				if(updateFileTitles) {
 					fileManager.updateFileTitles();
@@ -293,29 +304,58 @@ define(["jquery", "core", "google-helper", "dropbox-helper"], function($, core,
 			return;
 		}
 		syncRunning = true;
+		uploadCycle = true;
 		lastSync = core.currentTime;
-		onSyncBegin();
-
-		syncDown(function() {
-			syncUp(function() {
+		synchronizer.updateSyncButton();
+		
+		function isError(error) {
+			if(error !== undefined) {
 				syncRunning = false;
-				onSyncEnd();
+				synchronizer.updateSyncButton();
+				return true;
+			}
+			return false;
+		}
+
+		syncDown(function(error) {
+			if(isError(error)) {
+				return;
+			}
+			syncUp(function(error) {
+				if(isError(error)) {
+					return;
+				}
+				syncRunning = false;
+				uploadPending = false;
 			});
 		});
 	};
 	
 	synchronizer.forceSync = function() {
 		lastSync = 0;
-		this.sync();
+		synchronizer.sync();
 	};
 	
-	synchronizer.isRunning = function() {
-		return syncRunning;
+	synchronizer.updateSyncButton = function() {
+		if(syncRunning === true || uploadPending === false || core.isOffline) {
+			$(".action-force-sync").addClass("disabled");
+		}
+		else {
+			$(".action-force-sync").removeClass("disabled");
+		}
+	};
+	
+	synchronizer.init = function(coreModule, fileManagerModule) {
+		core = coreModule;
+		fileManager = fileManagerModule;
+		
+		synchronizer.updateSyncButton();
+		$(".action-force-sync").click(function() {
+			if(!$(this).hasClass("disabled")) {
+				synchronizer.forceSync();
+			}
+		});
 	};
 
-	synchronizer.isQueueEmpty = function() {
-		return syncUpQueue.length === 1;
-	};
-	
 	return synchronizer;
 });