The vast majority of iPhone and iPad users will not see the iOS 5 update until sometime this fall.
However, there is one new feature that is available now on the iPhone (iPod touch) and iPad: The ability to see and download apps that were purchased (including free apps) but are not currently installed on an iOS device. Here’s how you can find it on the iPhone. Tap the Updats icon on the bottom right of the display to see your list of updates. You’ll see a new area labeled “Purchased.” Tap that row.
You’ll see a list of all the apps you’ve purchased and a separate list of ones that were purchased but not on the iPhone.
This new feature is much more obvious on the iPad. The “Purchased” feature is a new icon to the right of “Updates” on the iPad.
The iPad purchased page can display either all the apps purchased for the iPad or just the ones that are not currently installed as seen in the screenshot above.
Prior to this update, the iPhone or iPad needed to be tethered to a Mac or PC running iTunes to see apps that were not currently installed on the iOS device.