iOS

iOS is to Apple mobile devices what Mac OS X is to the desktop computers. All smartphones and tablets made by Apple Inc. are shipped with the iOS operating system.

Since iOS is only available to be used on Apple smartphone and tablets, it doesn’t have anywhere near the number of shipments as its main competitor in Android. However, iOS is an excellent operating system that is neck and neck with Android, and sales would reflect that if Apple were to let it off its leash.

Jailbreaking is the iOS equivalent to rooting for Android. Unlike Android, Apple does its best effort to lock down the iOS operating system; thus making jailbreaking next to impossible to do with the modern-day versions of iOS.

Since iOS is designed strictly for mobile devices, the operating system is designed around the touchscreen input and not the keyboard or mouse like you would get from Mac OS X. iOS relies heavily on the use of applications. Outside of the apps, the operating system cannot do as many things as its desktop equivalent.