Remember how earlier you did not have the Purchases tab in iTunes App Store on iPhone? So if you removed some app from your device and wanted to reinstall it, the only option was to try to buy it again and if you already purchased it your card won’t be charged. But if you missed the name or the version (ex. Was it Angry Birds Rio or Angry Birds Seasons I had bought?) you would end up buying the second app.
So Dear Future Astronaut AB developed Reinstall My Apps which provided users with a searchable history of all purchased apps which can be reinstalled for free directly from the list. The app was completed and fully functional and submitted to Apple for a review. But Apple rejected it and, fortunately for the users but unfortunately for the app in question, introduced that missing feature directly into the App Store. So, now it can be only used as a good example of app development project.
Users who have bought a lot of apps can avoid the need of having to click the ‘Buy’ button and enter iTunes password in order to check whether they can reinstall it for free or will have to pay for it. This feature is especially important if there are more applications with very similar names or if the user has bought a particular version of an application. Reinstall My Apps can be installed on all devices connected to the same iTunes account and thus enable easy syncing of paid apps between devices. User privacy is protected since they can customize which apps will be shown on the list on other devices.