The S4 (left) looks almost identical to its predecessor, the Galaxy S3.
The camera on the back of the S4 (camera) is noticeably larger and Samsung has moved the position of the flash
Holding down the back button brings up a list of apps which can be used in split screen mode
Simply tap on the apps you want to use together for multitasking. Here we used the Gmail app and the web browser
Samsung has modified Android Jelly Bean. Swiping down from the screen with two fingers brings up a number of quick settings
Image quality on the S4's 5in screen looks superb. The device packs 1920 x 1080 resolution and 441ppi