So it was true. The iPhone 4S really didn't want to play nicely with the latest iOS 6.1 operating system. It hasn't taken Apple long to remedy that.iOS 6.1.1 has just been made available for the iPhone, a matter of days since issues were reported with the update and the iPhone 4S. As far as we are aware, the latest version of Apple's operating system is rolling out just to the iPhone 4S. Other models don't seem to have had any new upgrade offered.It's a 23MB update, with Apple simply saying the new software 'fixes an issue that could impact mobile performance and reliability for iPhone 4S'. If you remember, Vodafone did warn iPhone 4S owners not to download the original iOS 6.1 because of '3G performance issues', so it all adds up.Other users were also complaining of battery and overheating issues. Whether those have been dealt with by 6.1.1 isn't clear. We'll keep an eye on those Apple forums for that.