苹果iOS 4.2.1 (iOS 4.2)准备vs iOS 4.3.3 Apple iOS 4.2.1 (iOS 4.2) and iOS 4.3.3 are the most widely used iOS version and the latest version respectively. Though Apple introduced iOS 4.3 in March 2011 with its new iPad 2, many of the iPhone 4, iPad and iPod Touch users are still using iOS […]