Reviewed in Padfone 2 (Apps & Games)
Hybrid - Google Play free/install. This app is pretty much like Steam for Android games if you've been contributing to Humble Bundle when they have their Android games on, also their store has a range of Android games which you can download via this app directly to your device without the hassle of copying it from a PC.
Reviewed in Essentials for newbies
If you are looking to get games for your new Android, you should consider using Humble Bundle. Humble Bundle is a charity service, where you can pay what you want for various bundles of games - here among Android games. You use this app to download and install the apps you've bought there. You can save a lot and try many games you otherwise wouldn't have.
The Humble Bundle app is an easy way to install and update your games purchased through Humble Bundle. It can also send you (configurable) notifications about upcoming bundles so you don't miss another one!