Real Boxing (US$0.99)
Simply some of the best graphics you’ll see on a mobile. From beads of sweat to fountains of blood, the gory action will have you enthralled in this 3D boxing game. It sports over 30 fights, three belts and 20 opponents, which should keep you busy for a while. Just don’t get too carried away and launch your phone across the floor.
Everything Home (Free)
Take advantage of the S4's super-fast Internet connection and giant screen by letting Everything Home guide you. Just type or speak what’s on your mind and it’ll find everything locally on your phone, and online, associated with that. A simple but experience-expanding way to search beyond the limits of Google. It's still in beta, mind you – so you may encounter a few quirks along the way.
Floating Notifications (Free)
This does exactly what the name suggests. Unlike normal notifications, these pop up in a handy bubble on top of any app. One tap tells you what it is and another takes you to it, or you can double tap to get rid of the bubble. It's simple, effective and runs smoothly with the mega RAM of the S4.
More after the break...
Marvel Heroes Live Wallpaper (US$1.99 a month)
While the app is free, you’ll have to shell out for a live animation of your favourite hero on your lock screen. But that includes custom alerts like Daily Bugle headlines, screen tap actions, 3D graphics that can be viewed by rotating the phone, and character-specific widgets like clocks.
Nova Launcher Prime (US$4.00)
The beauty of Android is that you can customise it without having to jailbreak it. If you're not a fan of Samsung's cartoony TouchWiz interface then dial things back a notch with Nova Launcher, which offers custom icon packs and gesture controls, letting you set up your S4 just the way you want it.
SWIFTKEY Keyboard (US$2.44)
SwiftKey is the best touch screen keyboard we've ever used and its word predictions are so accurate, they actually scare us a little. The latest version includes emoji support and the option to split the keyboard up across the screen. You can even shrink it and move it around for easier one-handed typing, if you like.