Apple upgrades iPhone OS to version 3.1.3

Apple has released iPhone OS to version 3.1.3 (7E18), replacing the OS on all models of iPhone and iPod touch devices.

We have the following fixes:

• Fix for iPhone 3GS battery level reporting
• Fix for app crashes on launch
• Fix for app crashes while using Japanese Kana Keyboard

There's also a bunch of security fixes:

• Playing a maliciously crafted mp4 audio file may lead to an unexpected application termination or arbitrary code execution 
• Viewing a maliciously crafted TIFF image may lead to an unexpected application termination or arbitrary code execution
• A person with physical access to a locked device may be able to access the user's data
• Accessing a maliciously crafted FTP server could result in an unexpected application termination, information disclosure, or arbitrary code execution
• Mail may load remote audio and video content when remote image loading is disabled

I've installed it on my iPod touch and everything seems to work fine.