Say hello to Crystal, the only app you need to preview and prototype Sketch designs. Relied on by teams at Google, Apple and Expedia. Open Crystal on the same WiFi as your computer and start previewing your designs in realtime. Crystal refreshes on the fly as you modify your artboards in Sketch and auto-switches to your current Sketch artboard.
The app is totally safe to download. Crystal is developed by Smithy Productions and its category is Art & Design. On Google Play, the tool was rated 4.5 by its users.