Apple has pushed iOS 6.1.1 update out, but for now it is only available to iPhone 4S users. According to Apple, the update is designed to fix "cellular performance and reliability for iPhone 4S." While not specified by Apple, it is likely that this update has been released in order to fix the issue that UK carrier Vodafone warned users about last week. This update is only relevant to European iPhone users. We will have t wait to see if this update actually fixes the problems that iPhone 4S users were experiencing. However, given recent reports, there are plenty of other bugs for Apple to fix.