diff --git a/src/browser/components/MainPage.jsx b/src/browser/components/MainPage.jsx
index 83689b91..8c4aa4bb 100644
--- a/src/browser/components/MainPage.jsx
+++ b/src/browser/components/MainPage.jsx
@@ -38,7 +38,8 @@ const MainPage = React.createClass({
   propTypes: {
     disablewebsecurity: React.PropTypes.bool.isRequired,
     onUnreadCountChange: React.PropTypes.func.isRequired,
-    teams: React.PropTypes.array.isRequired
+    teams: React.PropTypes.array.isRequired,
+    onTeamConfigChange: React.PropTypes.func.isRequired
   },
 
   getInitialState() {
@@ -319,6 +320,7 @@ const MainPage = React.createClass({
             });
             this.props.teams.push(newTeam);
             this.render();
+            this.props.onTeamConfigChange(this.props.teams);
           }}
         />
       );
diff --git a/src/browser/config/AppConfig.js b/src/browser/config/AppConfig.js
index 06496970..c235db5c 100644
--- a/src/browser/config/AppConfig.js
+++ b/src/browser/config/AppConfig.js
@@ -1,12 +1,22 @@
 const settings = require('../../common/settings');
 const {remote} = require('electron');
 
-var config;
-try {
-  const configFile = remote.app.getPath('userData') + '/config.json';
-  config = settings.readFileSync(configFile);
-} catch (e) {
-  config = {};
+class AppConfig {
+  constructor(file) {
+    this.fileName = file;
+    try {
+      this.data = settings.readFileSync(file);
+    } catch (e) {
+      this.data = {
+        teams: []
+      };
+    }
+  }
+
+  set(key, value) {
+    this.data[key] = value;
+    settings.writeFileSync(this.fileName, this.data);
+  }
 }
 
-module.exports = config;
+module.exports = new AppConfig(remote.app.getPath('userData') + '/config.json');
diff --git a/src/browser/index.jsx b/src/browser/index.jsx
index 1c051744..18a7476a 100644
--- a/src/browser/index.jsx
+++ b/src/browser/index.jsx
@@ -14,7 +14,7 @@ const badge = require('./js/badge');
 
 remote.getCurrentWindow().removeAllListeners('focus');
 
-if (AppConfig.teams.length === 0) {
+if (AppConfig.data.teams.length === 0) {
   window.location = 'settings.html';
 }
 
@@ -33,7 +33,7 @@ function showUnreadBadgeWindows(unreadCount, mentionCount) {
   if (mentionCount > 0) {
     const dataURL = badge.createDataURL(mentionCount.toString());
     sendBadge(dataURL, 'You have unread mentions (' + mentionCount + ')');
-  } else if (unreadCount > 0 && config.showUnreadBadge) {
+  } else if (unreadCount > 0 && AppConfig.data.showUnreadBadge) {
     const dataURL = badge.createDataURL('•');
     sendBadge(dataURL, 'You have unread channels (' + unreadCount + ')');
   } else {
@@ -44,7 +44,7 @@ function showUnreadBadgeWindows(unreadCount, mentionCount) {
 function showUnreadBadgeOSX(unreadCount, mentionCount) {
   if (mentionCount > 0) {
     remote.app.dock.setBadge(mentionCount.toString());
-  } else if (unreadCount > 0 && config.showUnreadBadge) {
+  } else if (unreadCount > 0 && AppConfig.data.showUnreadBadge) {
     remote.app.dock.setBadge('•');
   } else {
     remote.app.dock.setBadge('');
@@ -82,11 +82,16 @@ function showUnreadBadge(unreadCount, mentionCount) {
   }
 }
 
+function teamConfigChange(teams) {
+  AppConfig.set('teams', teams);
+}
+
 ReactDOM.render(
   <MainPage
-    disablewebsecurity={config.disablewebsecurity}
-    teams={config.teams}
+    disablewebsecurity={AppConfig.data.disablewebsecurity}
+    teams={AppConfig.data.teams}
     onUnreadCountChange={showUnreadBadge}
+    onTeamConfigChange={teamConfigChange}
   />,
   document.getElementById('content')
 );