My Pinterest Clone - Please review and test

Just claimed the last certificate by finishing the back-end project and I was wondering if I can get a review, especially if anyone can log in with twitter and see if it is working fine. Any honest critique (of design or code) would help me tremendously to improve my skills.

repo :

Regarding the project, obviously it is very difficult to fully clone the entire functionality of pinterest as I am only one person but I tried doing the main functionality of the application, which is to post-pin and save pictures.
For instance the real application has a way to match your saved images with similar ones online and show you those, it also allows you to categorize your pins into boards and does many other fancy things.
But still, I feel like I have learnt a lot just by getting this far.