The post made by denise was one of my starting points. I have tried to add as much functionality as I could keeping it doable in a 3 months period. My goal is to make a well tested and documented app that can be updated afterward.

For development I will use an agile like method. This means I will work in sprints. After each 2-3 week sprint I will have an usable app ready to be tested. At midterm I want to have first "beta" version ready to be downloaded and tested by the community in order get feedback.

One of things that I think will be hard to do is upload userpics and manage friends and subscriptions.