BranchList is a to-do list app that allows you to create multi-level tasks. Each item can become its own new list and you can go to one level down as many times as you want.
RSS Reader or JellyReader is an app that stores all your articles on Google Drive and Dropbox! The data is completely self-hosted on your personal cloud, so it can never go down or go away.
Two-player tetris powered by NimbusBase on top of Google Real-Time. Just invite someone, send them your link and you can play each other in the same game!
This is a Reddit clone that uses Google Cloud Storage as a backend. It's an experiment that shows how NimbusBase can use a third party cloud storage to store public data.