Apple has released iOS 5.1.1, a minor update to the operating system for the iPhone, iPad and iPod touch. This update includes fixes for three security issues: one involving URL spoofing in Safari, and two it WebKit, the HTML rendering framework, which protect against vulnerabilities that could be exploited by booby-trapped web sites.
This update is available directly on iOS devices in Settings > General > Software update, or it can be downloaded and installed in iTunes when a device is connected to a computer.
