As part of my ongoing research into MVVM architecture, databinding, RxJava 2, and Dagger 2 on Android, I built a small Android app that utilizes the Guild Wars 2 API (https://wiki.guildwars2.com/wiki/API:Main). Right now, there’s only a few API responses being utilized as part of this project, but it has been useful for understanding more about MVVM, RxJava 2, and Dagger 2.
Overengineered? Yes. A work in progress? Definitely.