Dmitry and Bernd and I were talking a bit about Sign In & Register visual design patterns. I was going to send them some iOS screenshots I had taken a while back, but remembered stuff is a little different in the Android apps versions - not a ton, but enough.
Here you go. Sort by Title.
Here were the iOS mocks I saw for Wikipedia. Monte is iterating on this with Vibha and Moiz, I think.
No doubt there's a dance involving screen real estate, soft keyboard up/down considerations in light of screen real estate, careful labeling & icon-ing of progressive actions and keyboard buttons, and prevailing style(s). Plus in our case we don't do third party authentication at the moment; not sure if "anonymous" third party authentication (e.g., Wikipedia user = LikesToEmail (third party authenticated user sequence number 1234567890)) will ever be an option .
I know this is mostly obvious stuff, just thought I'd share some screencaps in case others hadn't seen them.
-Adam