For example, if you downloaded iDos before Apple removed it from the store, then restored your device there would be no way to get iDOS back. With the purchased tab on the appstore you can get any of these back that you had previously purchased.
Engadget decided to give it a whirl, testing with an iPhone 3GS humming along on iOS 4.3.3. Upon browsing the Purchases section of the App Store, he beheld Tris, an app that hasn’t been available in nearly three years. He pressed the iCloud icon and within seconds, the ol’ Tetris clone was back in action.