In yet another surprising move, Apple unexpectedly released its new iPhone 3.1.3 firmware for iPhone 3G/3GS and iPod touch. Something important to note, 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, you have to connect your iPhone with your computer via usb and start iTunes. You will see a message, just simply click on “Download and Install” button to get on to the new iPhone OS 3.1.3 firmware.

iPhone 3GS

Caution:  Do not update your iPhone to OS 3.1.3 if your phone is currently jailbroken or unlocked on firmware 3.1.2. Be patient and wait for the new jailbreaking and unlocking tools prior updating your device else you may loose the capability to jailbreak or unlock your device in future.

The new OS 3.1.3 Firmware improves accuracy of reported battery level on iPhone 3GS, resolves issue where 3rd party apps would not launch in some instances and fixes bug that may cause an app to crash when using the Japanese Kana keyboard.

Stay tuned for the updates on OS 3.1.3                 [via Redmondpie]