Except all the apps you can download from F-droid, here is some additional ones:
1. 安能饭否
https://github.com/fanfoudroid/fanfoudroid
http://code.google.com/p/fanfoudroid/
2. foursquared (Abandoned)
https://code.google.com/p/foursquared/
3. Beam (Android XMPP)
http://beem-project.com/
4. Replica Island (Game)
Development Blog: http://replicaisland.blogspot.com/
http://code.google.com/p/replicaisland/
Talk link about Android Game …