What an absolute dogs dinner the Atom app is - at least on Android. I've had a look through the demo account, and it's almost unusable. I appreciate they're trying to differentiate themselves from conventional banking, but it strikes me that a gimmicky interface probably isn't going to win them many plaudits.
The performance is poor - but more importantly, the UI concepts are awful. With a new interface, you have to give the user a lot of clues around how to navigate, but everything's a mystery until you click. Even then, there are some things that don't respond unless you swipe or flick them. It has all the hallmarks of a design where someone senior has been saying 'MAKE IT MORE DIFFERENT, WE'RE DIFFERENT'.
Finally - they keep on going on about biometric security. That's all well and good, but it's still hackable, but even if you find out you've been hacked, you can't change your face. I'll stick with a PIN for now.