In late January, Apple began rolling out an update to Ios 6.1. However,
it would appear that this update would cause a bug that made it
difficult for iPhone 4S users to connect to the 3G network in some
networks. Some European operators - such as Vodafone UK and 3 Austria - cause even to go out and warn their customers to download the update if you have an iPhone 4S, reports Cult of Mac.
Can be downloaded wirelessly
On Monday evening, Apple released a new Ios version (6.1.1), which
therefore must fix these problems that can affect the "performance and
reliability when using the mobile network" that Ios 6.1 brought with it
to some iPhone 4S users.
Ios 6.1.1 seems to only be available for the iPhone 4S, and will go to download wirelessly.