As an android user, this is not at all the same app we've had for a while now. The UI is very different and takes some getting used to. There's a lot more animation and transitions, they're really taking advantage of having everything in one screen. (As opposed to android where everything is broken up into activities which have very limited transitions)

I'd be surprised if they polished anything, considering you can't exactly reuse Java code when writing an Obj-C app. They just have a lot of very talented engineers and actually cared about making it nice.