A recent series of posts from Milan Babuškov at Bigosaur covers the development, from start to finish, of a complete Android game called "Drone Invaders" over the period of 23 days for the October challenge of the Ludum Dare competition. There is one post for each day, some covering game mechanics and brainstorming, but most tracking the technical difficulties, thought processes behind tool and library choices, and methods and tips learned along the way. Here is the completed product:
Useful posts include, for example, Day 18 (which addresses sprite collisions with a circle shape) and Day 15 (which describes how to use the Android back button with libGDX). Anybody interested in Android game development, or Android development in general, should check out the full series for an extremely detailed how-to covering the complete development of an Android game.