The iOS update fixes issues associated with the keyboard, voice over controls, AirPlay and Safari, with the App Store finally recognising the apps that you have previously purchased, if you either installed them before or have had to transfer to a new iPhone device.
The Personal Hotspot feature has been made available to all, allowing users to share their 3G connections with up to five devices, three of which use the iPhone’s WiFi connection and the other two Bluetooth or USB.
The updates will of course remove your jailbroken status and carrier unlocks, so if you do update you should make sure you backup your SHSH blobs via Cydia.
To download, connect your device to iTunes and check for updates. The rest, Apple will take care of. If you want the direct links, here you go:
– iPhone 4
– Apple TV