Apple on Tuesday released a new version of its iPhone operating system. The update is compatible with all iPhone and iPod touch models. According to the information provided with iPhone OS 3.1.3, the update improves accuracy of the battery level on the iPhone 3GS; an issue is resolved where some third-party apps would not launch; and a bug has been fixed that caused apps to crash when using the Japanese Kana keyboard.
The update can be downloaded directly from iTunes by plugging in your iPhone and clicking the “Check for Update” button.