Vodafone was among the mobile network operators that warned iPhone 4S owners not to upgrade to the iOS 6.1 because of reported 3G problems.
Vodafone said iOS 6.1 affected performance on 3G for users of the iPhone 4S and some customers may occasionally experience difficulty in connecting to the network.
The new release, which should be available through the smartphones or can be downloaded directly from Apple, is only available for iPhone 4S users.
In the support section of its website, Apple said: "This update fixes an issue that could impact cellular performance and reliability for iPhone 4S."
While Apple has responded quickly to warnings about 3G problems, there has been no response to complaints that the latest iOS was affecting battery life.
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Apple's support forums feature numerous reports from iPhone owners who say that they are experiencing problems with battery life since upgrading to iOS 6.1.
However, some users say restoring the handset using iTunes solves the problem, according to the Telegraph.
The Guardian noted that Apple also does not appear to have fixed problems reported with all models of iPhones running iOS 6 when connecting to Microsoft Exchange servers.
This problem has led some corporate users to block certain functionality relating to meeting invitations.
But Apple has not responded to requests to clarify when it plans to fix the problems with Exchange accounts, the paper said.