This is the secure droid you are looking for.
This talk was done on Pixels Camp 2016 and aimed to show developers the best practices for secure development in the Android platform.
We walked through the topics such as Networking, Storage, IPC, Unintended Data Leakage, among others. Also covered some of the new security features coming to developers on Android Nougat.
Here are the Android Projects I developed with the vulnerable code for each vulnerability:
https://github.com/clviper/pixelscamp_talk_resources