Do you have an app that refuses to update or a new app that is stuck in the middle of the download? There are a number of reasons why an app might get stuck downloading, from an authentication issue with the App Store to some garbled settings on the device itself. Don't worry, if you do have this problem, these steps should fix it.
Tap the app as if to run it.
Sometimes, a download will stall out due to a poor connection or similar reason, so make sure you have a good connection to the Internet. So the first thing to try is simply launching the app. This can force the iPad to recognize the app hasn't completely downloaded and it will kickstart the process.
Check for pending downloads in iTunes.
Another frequent problem that causes apps to stop updating is an issue downloading a song, movie or podcast in the iTunes store. If an item is stuck in the queue with higher priority than the app you are trying to install or update, it can get stuck downloading. Launch the iTunes app and check the "Downloads" tab. If something is stuck, try deleting it, and if it won't delete, try deleting all of the pending downloads below the one that is stalled.
Reboot the iPad.
After checking the most common reasons for an app not to update or download completely, it is time to go with the most popular troubleshooting step: reboot the device. Remember, it is not enough to simply suspend the device and wake it up again. In order to give the iPad a full refresh, you will need to power off the device by holding down the sleep/wake button for several seconds and following the instructions on the screen. Once it is fully powered down, you can boot it back up by pressing the sleep/wake button again. This process will give the iPad a clean start and has a tendency to solve many problems.
Download a new app.
It's possible for the iPad to get hung in the authentication process. The easiest way to solve this issue is to download a new app, so try picking out a free app and installing it onto the iPad. Once it installs, try tapping the app that is stuck to see if attempting to launch the app triggers the download process.
Sign out of your Apple ID.
If going through the authentication process by downloading an app doesn't work, sometimes simply logging out and logging back in will do the trick. You can sign out of your Apple ID by going into the iPad's settings, choosing iTunes & App Stores in the left-side menu and tapping where it displays your Apple ID. This will bring up a popup menu that will allow you to sign out. Once you are signed out, sign back into your Apple ID and try launching the app again.
Restart your Wi-Fi router.
While rare, it is possible for your router to be the root of the problem. This isn't intentional. Your router isn't mad at you or anything, but because it has a built-in firewall and manages multiple devices, it can get a little mixed up at times. Try powering down the Router and leave it off for a full minute before turning the router back on. It normally takes a router a few minutes to power on and get connected to the Internet again. Once all of the lights come back on, try signing in with your iPad and touching the app to see if the download process starts.
Reset all sttings.
The last trick in our arsenal is to reset the iPad's settings. Don't worry, this won't completely wipe your iPad, but it may cause you to make any tweaks you've made to your settings again and you might find yourself signing back in to various apps and websites like Facebook and Twitter. But other than clearing out your settings, this process will leave all of your apps, documents, music, movies and data alone.
To reset your settings, go into the iPad's settings and choose General from the left-side menu. Next, scroll all the way down and tap Reset. On this screen, choose Reset All Settings. This will prompt you before continuing with the reset.
This is one of the most common cures for an app that is stuck during an update or an app that won't download completely, but because it can change any custom settings back to default, this step is saved for last.