Apple has released a minor iOS update version 5.1.1 which fixes a couple of bugs along with some reliability improvements. According to the update details, it addresses the HDR photo shooting issue when activated from the lockscreen, switching issue between 2G and 3G networks on iPad, AirPlay, Safari bookmark syncing and issues related to purchases.
You can either upgrade this over the air (OTA) if you’re on the newer iOS or via iTunes through USB cable.
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