Earlier today Apple updated their mobile platform to version iOS 7.1.2 which Improves iBeacon connectivity and stability, Fixes a bug with data transfer for some 3rd party accessories, including bar code scanners, and Corrects an issue with data protection class of Mail attachments. But it seems that some users are having a stall issue when trying to update.
While updating the device some users say it will freeze half way through leaving you with the turning gears screen, but luckily there is an easy fix for this issue.
All you have to do is a hard reboot, which is done by holding down the Home and sleep/wake button until the screen goes dark, and you see the Apple logo on the screen, release both buttons and wait for the phone to reboot.
Check if the update was completed by going to Settings>General-About, here you should see your device is on iOS 7.1.2, but if some some reason the update didn’t go through just go through the update process again.