Additionally, not all mobile apps are the same; e.g., 7 days is certainly too long for games, but probably just fine for a calendar app. The Android market alr

Additionally, not all mobile apps are the same; e.g., 7 days is certainly too long for games, but probably just fine for a calendar app. The Android market already lets you customize your trial duration, though in a second-best manner—you upload both a demo and a regular version of the app. Of course, there are a bunch of problems, like trying to migrate data.