I tested on a 4.2 android and I did't notice the issue. Bad thing about mobile is that is pretty hard to debug and since android has so many versions is even harder.
iPad 4 working with chrome and safari too
S3 -had the issues
S1 - fresh factory ROM untouched - browser login is ok but when i clicked in the password field the filed was moving up and down on the screen. it worked but keep flipping up-down :/ also had the keep loading circle issue with the images
Just to give some extra info. I'm using Nexus 4 (Andorid 4.4.2) using the default Chrome. When clicking on any of the text fields (login or creating an account) as soon as the keyboard pops up the login form vanishes and it returns to what ever page it was on.
The contact page fields do not have this problem. It appears to be related to the overlay from the menu when the keyboard is selected.