Mobile Apps
iphone apps
iPhone are currently the front runner with mobile apps - more people download from Apple's appstore than its nearest rival range from Android.
Android apps
With HTC entering the Android market, the userbase has grown and grown throughout 2011. Apps for the Android market have now become a serious contender to Apple.
Windows 7 apps
Still in a minority with regards Microsoft's own store, Windows 7 mobile apps are one to watch throughout 2012.