iOS 5 might be the most popular version of Apple's mobile OS yet. When Apple released it as a digital download through iTunes on Oct. 12 the heavy demand almost crashed Apple's servers.
Available for the iPhone 3GS, iPhone 4, iPhone 4S, and all iPads, this update includes more than 200 enhancements for a reasonable price--it's free. This visual tour focuses on 11 major enhancements and four new apps introduced with iOS 5.
Another great feature in iOS 5 is iCloud, Apple’s replacement for its subscription-based cloud service MobileMe. Unlike MobileMe, which will be discontinued next summer, iCloud is free. And if all your iOS devices are running iOS 5, you can even ditch your computer and just use iCloud--the devices are independent. For example, iCloud keeps a list of apps you've purchased. You can install these over the air at any time, instead of going through iTunes like before.