The iPhone 5S (marketed with a stylized lowercase 's' as iPhone 5s) is a smartphone that was designed and marketed by Apple Inc. Part of the iPhone series, the device was unveiled on September 10, 2013, at Apple's Cupertino headquarters. It was released on September 20, 2013, along with its lower-cost counterpart, the iPhone 5c.
The iPhone 5S includes major internal upgrades but maintains almost the same external design as its predecessor, the iPhone 5, although the 5S received a new white/gold color scheme in addition to white/silver and space gray/black. A redesigned home button with Touch ID, a fingerprint recognition system which can be used to unlock the phone and authenticate App Store and iTunes Store purchases, was introduced. The camera was updated with a larger aperture and a dual-LED flash optimized for different color temperatures. The 5S also introduced the A7 64-bit dual-core processor, the first 64-bit processor to be used on a smartphone, accompanied by the M7 "motion co-processor".