ngmoco’s freemium games have been a success in the iOS (iPhone/iPad) market. ngmoco’s We Rule, for example, is the 69th highest grossing app in Apple’s App Store despite being a free game that has been available for over a year. They do this by enticing players to make in-app purchases to obtain tokens that can be exchanged for virtual goods. ngmoco games also provide a social component that lets you cooperate and compete with other players.
This monetization model and platform for free games is now available for Android in English-speaking countries.
The Mobage gaming platform is available for free in the Android Market. It provides access to more than 20 free games including We Rule and Pocket Frogs which iOS users will be familar with.
Mobage (Android Market)
With 82 reviews in so far, user experience looks like a mixed bag with 33 giving it 5 stars (40%) and 31 givig it 1 star (38%). My guess is that this is a result of Android platform fragment where the app runs fine on some phone models and crashes on others.
[Mobage] What is the Mobage Beta? (Mobage support Instant Answers)