The Apple iPhone 4s in black runs on iOS. With a 3.5-inch display, it provides clear visuals in 640 x 960p resolution. This iPhone is great for taking high quality images and videos with the 8MP front camera and a VGA secondary camera. Its 32GB memory space can store plenty of apps and other media. This device is unlocked and compatible with Vodafone, EE, O2, Three Carriers.