android sdk design Metrics and Grids
48dp Rhythm
Touchable UI components are generally laid out along 48dp units.
Mind the gaps
Spacing between each UI element is 8dp.
http://developer.android.com/design/style/metrics-grids.html
Android provides two system themes that you can choose from when building apps:
- Holo Light
- Holo Dark
http://developer.android.com/design/style/themes.html