Improving what was already a wildly successful formula, the Humble Bundle has added Android to its latest pay-what-you-want promotion. Folks willing to dole out up to $5.70 (a penny below the current average amount submitted) will receive a copy of three hot indie games including Edge, Osmos HD and Anomaly: Warzone Earth. If you're willing to meet or exceed the average submission of $5.71, you'll get World of Goo as well.

As with previous events, all four games are available completely DRM-free (or via Steam, if preferred) and they work across Windows, Mac OS X, GNU/Linux and for the first time, Android. Compatibility with Google's smartphone operating system is more involved, so you might want to scan the system requirements before purchasing. For instance, Anomaly requires Android 2.3 or higher (though the G2 with Android 2.2 works).

Although there are "only" four games currently offered, the Humble Bundle has made a habit of adding more games as the promotion unfolds (you receive them even if you pay beforehand). The group also throws in soundtracks for all the games. A bargain to be sure, but folks who bought previous Humble Bundles should beware: World of Goo was included in the first Bundle promo in May 2010 and Osmos was offered in the second.

As of writing, more than 46,500 have sent over $266,000 with the top contribution being $1,660.19 from @tantepose. Linux users represent the highest average submission at $7.72, Mac users trail at $6.77 while those on Windows sent $5.14 on average. You can divide your payment up between the Humble organizers, game developers and charities such as the EFF. PayPal, Amazon Payments and Google Checkout are accepted.