Google has enabled a feature that developers are sure to love. Much like iOS, developers can now offer in-app billing for their apps. This means they could offer you an app, then add levels or features and bill you for them from within the app. It uses the same checkout system as the Market itself and Google will get a 30% cut from all proceeds.

This new system will also let developers offer a “try-and-buy” feature. This means that you could download a free trial of an app from the Market that might be fully functional for xx number of days, or even a limited version of the app. Then after the trial is up, you could do an in-app purchase of the full version without having to re-download the full app.

There are several apps and games that are already using this feature.

Source: SlashGear