Android Niceties is a showcase of Android design, and I'm finding it great to get some inspiration for what is possible in Android.
Interestingly, Xero (which is not a native app) is featured at the top. It is a nice looking app tho.
The Android UX is the main part I have a love-hate relationship with. Holo goes a long way to making it nice, but drop back to 2.2 or 2.3, and my eyes are bleeding. Scrolling of lists is a big part of it, because lists are such a huge part of most mobile apps.
Unsurprisingly, this is mostly Holo themed, and I'd assume they are using the likes of ActionBarSherlock and the various other bits that make Android mostly standard from 2.2 to 4.2.