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README.md

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 # electron-mattermost
-Desktop app for Mattermost that run on Electron
+Desktop app for [Mattermost](http://www.mattermost.org/) that runs on [Electron](http://electron.atom.io/)
 
-Mattermost: https://github.com/mattermost/platform
+## Features
+* Badges for unread channels
+* Desktop notification
+* Stay in taskbar (Windows)
+
+## Usage
+1. Download and unarchive a file from [release page](http://github.com/yuya-oc/electron-mattermost/releases).
+2. Launch electron-mattermost.exe or electron-mattermost.app
+3. After first launching, please input URL for your Mattermost team. For exmaple, `http://mattermost.example.com/team`.
+4. Ctrl or Command + Q to exit.
+
+Configuration will be saved into Electron's userData directory:
+* `%APPDATA%\electron-mattermost` on Windows
+* `~/Library/Application Support/electron-mattermost` on OS X
+* `~/.config/electron-mattermost` on Linux
+
+## Testing
+Node.js is required to test this app.
+
+1. Clone or download the source code.
+2. Run `npm install`.
+3. Run `npm start`. (If you have gulp, `gulp serve` has live-reload.)