Apple has released iOS 6.1.1 in the form of a 23MB over-the-air update for iPhone 4S users to address bugs that have accompanied the iOS 6.1 update released this month.

The update comes after carriers in the UK warned users about upgrading to iOS 6.1 over the weekend, citing issues with 3G connectivity. Several users have also reported issues with battery and overheating.

There's no word on official bug fixes, though Apple does say: "This update fixes an issue that could impact mobile performance and reliability for iPhone 4S."

The iOS 6.1.1 update was in testing for members of Apple's developer program from 6 February. It seems Apple worked quickly to get this update out to fix the many issues users were seeing.

We've reached out to Apple for word on official features and bug fixes, as well as when the iPhone 5 may see the iOS 6.1.1 update. You can download the update from the source link below.