Amazon has recently introduced a new shopping app for Android. Amazon Underground lets you do your shopping for apps and games for free. By free we mean the apps offered are complete with all the premium features. No need to pay extra for in-app items because the titles included are free versions of popular paid apps like 'Goat Simulator', 'OfficeSuite Professional 8', 'PhotoSuite 4', 'Star Wars Rebels: Recon Missions', 'Frozen Free Fall', 'Looney Tunes Dash!', and 'Angry Birds Slingshot' among others.