Apple has unexpectedly released the new iPhone 3.1.3 firmware for iPhone 3G/3GS and iPod touch. This is not the same version which runs on the newly announced Apple iPad (OS 3.2). To update to iPhone OS 3.1.3 Firmware, all you will have to do is to connect your iPhone with your computer via usb and start iTunes. You should now see a message as shown below. Simply click on “Download and Install” button to get on to the new iPhone OS 3.1.3 firmware.
Note: Do not update your iPhone to OS 3.1.3 yet if your phone is currently jailbroken or unlocked on firmware 3.1.2. Wait for the new jailbreaking and unlocking tools before updating your device or you may loose the capability to jailbreak or unlock your device in the future. You have been warned!
Change log for iPhone 3.1.3 is as follows:
* improves accuracy of reported battery level on iPhone 3GS
* resolves issue where 3rd party apps would not launch in some instances
* fixes bug that may cause an app to crash when using the Japanese Kana keyboard