0 done or available from within an app (= piece of software for your phone or computer that has a particular purpose):
The developers eventually switched to a free-to-play model supported by in-app purchases due to unbelievably high piracy.
The 205 and 103 trains are available as in-app purchases.
Artillery is upgradable via in game currency earned through missions, or by through in-app purchases.
This version introduced in-app purchases of digital goods, allowing for add-ons to be purchased within applications.
Chair did not rebalance the game to incentivize in-app purchases.
The version 3.0 update added an in-app photo library with editing features.
The version is free-to-play, but is different from other versions in removing some save points and relying heavily on an in-app purchase system.
Equipment can be purchased with either the goldball currency earned through gameplay or via in-app purchases.