This past weekend, popular application discover app AppGratis was removed from Apple’s App Store. Many had correctly assumed that the application was pulled from the store because of Apple’s Developer Guidelines 2.25 clause:

Any app that functions too similar to Apple’s own App Store, even if it routes users to complete the download via the App Store, will be rejected. If they already exist on the store, they will be removed. This Apple policy became stringent following the release of iOS 6 last fall.

While the app was removed for breaking this policy, AllThingsD reports that Apple has confirmed that the app was also removed for abusing Apple’s push notification system.

Discovery apps that utilize a different, non-promotional business model seem to be safe.