They're at least working on making that as easy as possible on Android: https://github.com/mozilla-mobile/android-components/ https://github.com/mozilla-mobile/

They're at least working on making that as easy as possible on Android: https://github.com/mozilla-mobile/android-components/ https://github.com/mozilla-mobile/android-components/ As I understand it, that should also make it relatively straightforward to switch between Servo and Gecko, as a developer. But I'm not an Android dev, so take that with a grain of salt.