Restore using iTunes: You can also try restoring your iPhone via iTunes. Plug your iPhone into your computer using your USB cable, and select your iPhone from the source list. Go to the Summary tab, and then select Restore iPhone: This will create a backup of your phone's settings, and then download and install a fresh copy of iOS and revert your phone to default settings. You can then put your data back on your phone by selecting Restore Backup from under the Backups heading.
Dealing with a stuck Android phone
Force-close an app: If you need to force a hung app to close, go to your phone's Settings app, then tap Apps. Swipe over to the Running tab, select the app you want to close, then tap the Stop button. If you don't see the troublesome app in the list, tap the Show Cached Processes toggle in the upper-right corner of the screen.
Restart your phone: Restarting your phone can help clear up stubborn problems. To do so, hold down your phone's sleep/power button for a few seconds until it asks you if you really want to turn off your phone. Confirm that you do, and your phone will power off. Once it's off, hold down the power button again until the screen turns on; your phone should be up and running again after a few moments.
Force-restart your phone: The standard shut-down-and-restart method may not work if your phone is frozen, in which case you may have to force your phone to restart. Unfortunately, it's a little more complicated on Android than it is on iOS, because different phones may have different hard-restart methods. You can force many Android phones to shut down, however, by holding down the power button and volume-up button until the screen goes dark. From there, power on your phone again by pressing the power button for a few seconds. If the volume-up button doesn't work, try the volume-down button. If this doesn't work, refer to your phone's documentation.
Remove the battery: If your Android phone is frozen solid and it has a removable battery, the easiest way to force-restart it is to simply remove the battery. Pop off the battery cover, remove the battery for a few seconds, put it back into place, snap the battery cover back on, then turn your phone back on by holding the power button down for a few seconds. You should use this method only if the standard method of powering off and restarting your phone fails, however.
Restore to factory defaults: Maybe you decided that trying to troubleshoot an issue just isn't worth the hassle. If so, you can reset your phone entirely and restore it to factory defaults. To do so, open your phone's Settings app, scroll down, and tap the Backup and Reset menu. Next, look for Factory data reset, and tap it. Your phone will ask you to confirm that you want to do the deed; once you do, it will restore itself to pristine, fresh-from-the-factory settings.
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