If you sign up for an account via Facebook login in the browser it works great -- you're redirected to Facebook to sign-in and give permission. But when I want to login in the Android app with Facebook, a window opens still in the SuperBetter app, asking for my Facebook password. That's not cool, and it's dangerous for users. There's no way for me to know that I'm giving my Facebook password just to Facebook; users shouldn't ever have to give their Facebook password to SuperBetter.