Personally I’m really excited about the new design language/framework/guide from Google to be all encompassing across web, mobile, tablet, TV. I talked recently at a local meetup about some of the cool things in material design followed by a good debate about what material design is about. The main place to head to is google.com/design
Here’s some other resources:
- Short video intro to showcasing some of the material visual elements and interactions
- Collection of material design elements selected by Roman Nurik on Dribbble
- Android UX course on udacity
- Slide deck from Romain Guy
- Google IO schedule app – has good examples of material running on Android 4-4.4 and on L. Discussed in this article, and the video walk through of the article is here.
While we are on the subject of design here’s a link to Designer cheat sheet for Android it’s very much based on holo but I’m sure as L preview is released these tips will be updated.