iOS versus Android
The two most popular smartphone Operative systems are iOS and Android. Windows phones are always behind them, and others are even less popular (Linux, Firefox and etc.). Although the smartphones with these OS have the same purpose, and their user interface is similar, there are many differences between them.
The first thing you must know is that Android is made by Google and iOS by Apple. Android is far more customizable, user can change almost anything. On the other side, iOS is very limited. But, you can jailbreak it (very easy process, but you lose warranty) and then you can change everything you want. Even then you cannot use widgets, except in notification center. Every version of Android OS has widgets.
There are many speculations about patent stealing between iOS and Android. These companies were several times in court, but details of their agreement are unknown. You must know that the initial release of iOS was on July 29, 2007 and for Android, September 23, 2008.
As you probably know the biggest difference between these two Operative systems, are their smartphone support. iOS is designed specially for Apple IPhone. Android is used by almost any smartphone manufacturer. Because of this, iOS have one advantage. It is made for one smartphone, with one system configuration, so it is much more reliable than Android. This allows it high performance on any iPhone model. If you remember, iPhone 3GS, which had a factory version of iOS 4, worked perfectly on iOS 6.1.3! Android smartphones have only one OS upgrade available. And it is a common problem that after that phones work slower and have more bugs. In addition, iPhone models are very expensive, if you are buying them outside US.