Overheating Phone from Apple

There have been mentions that the most recent update from Apple for Iphone and Ipod touch (v.6.1) has been creating problems with the battery. It has only been affecting Iphone recently and Apple as saying that they realise that it is a problem and is trying to fix the problem as quickly as possible. The problem that people have with the Iphone and the battery is that it drain's the battery extremely quickly. Also that it causes overheating. Although it's only with Iphone 4S with the update with this problem. Apple is giving no comment on what the problem is and why the latest version is causing the battery draining quickly and overheating. There have been rumours that its because it's using 4G network and it is overloading the phone.