Many of those who just bought an iPhone, an iPod Touch, an iPad tablet or a Mac and started buying applications from the App Store wonder what happens to the applications they bought from the store when they restore (reinstalling the operating system). The answer is extremely simple: all applications purchased/downloaded from the App Store are automatically associated with your Apple ID and can be reinstalled for free regardless of how many restores you make as long as they are available in the App Store. The applications available in an Apple ID can be installed on any iDevice/Macs, if they are compatible, but an application can be installed on a maximum of 5 iDevices/Macs and no more. When I say that it can be installed on 5 iDevices, I mean 5 different iPhone/iPad/iPod Touch terminals or Macs, this being the maximum limit imposed by Apple. After you have installed an application on 5 different iDevices/Macs, you cannot install it on another terminal and you must buy/download it again for free using another Apple ID.
In Cydia, things are similar, except that there you don't log in with an Apple ID, but using a Facebook account or a Google account, and all the tweaks and applications bought there can be reinstalled at any time, but still on a maximum of 5 iDevices. The free applications and tweaks in Cydia are not associated with a Facebook/Google account, so only those you purchase will be displayed in an account. In Cydia, things are simpler, but the limitations of the App Store are kept even if we are talking about another store.
In conclusion, you can make any restores you want, the applications already bought/downloaded from the App Store will always be available for your iDevices. The same system applies to music, movies or books.
