Start previewing your designs from Sketch in realtime on your Android device!
Open the app and find your computer on your local wifi network. Click to connect and you're mirroring artboards straight away, without any companion Mac app!
If you're on flaky connection or corporate network, fear not, as USB support is provided with a helping hand from the Crystal Mac app. Download the app from https://crystal.smithy.productions/#companion and carry on using Crystal as normal over a cable.
Crystal will always be free, but you're welcome to donate if you appreciate the work design + development that's gone into this. That's the only reason for the in-app purchases - none of the app is locked behind a paywall.
This is a companion app for a Mac design app called Sketch (sketchapp.com). Trying to use it for anything else, like watching movies, playing games or browsing the web will probably result in a sub-par experience.