How to Update an iPad App from the App Store
Every so often the developer of an iPad app releases an update. If an update awaits you, a little number in a circle appears on the Updates icon at the bottom of the iPad screen. Follow these steps to update your apps from your iPad:
Tap the Updates icon if any of your apps needs updating.
If you tap the Updates icon and see (in the middle of the screen) a message that says All Apps Are Up to Date, none of the apps on your iPad requires an update at this time. If apps need updating, they appear with Update buttons next to them.
Tap the Update button that appears next to any app to update it.
If more than one app needs updating, you can update them all at once by tapping the Update All button in the upper-right corner of the screen.
If you try to update an app purchased from any iTunes Store account except your own, you’re prompted for that account’s ID and password. If you can’t provide them, you can’t download the update.