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. iPhone 5S SIM Tray. The iPhone's nano-SIM card tray is made of aluminum.
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".
The iPhone 5S was the first Apple device to ship with iOS 7, which introduced a revamped visual appearance and other new features. Designed by Jonathan Ive, iOS 7 departed from skeuomorphic elements used by previous versions of iOS in favor of a flat, colorful design. Among new software features introduced to the iPhone 5S were AirDrop, an ad-hoc Wi-Fi sharing platform; Control Center, a control panel containing a number of commonly used functions; and iTunes Radio, an internet radio service. Earphones known as EarPods were included with the 5S, and Apple released accessories including a case and a dock.
Reception towards the device was generally positive, with some outlets considering it to be the best smartphone available on the market due to its upgraded hardware, Touch ID, and other changes introduced by iOS 7. Some criticized the iPhone 5S for keeping the design and small display of the iPhone 5, and others expressed security concerns about the Touch ID system. Nine million units of the iPhone 5S and iPhone 5C were sold on their weekend of release, breaking Apple's sales record for iPhones. The iPhone 5S was the best selling phone on all major U.S. carriers in September 2013.
The iPhone 5S was succeeded as Apple's flagship smartphone by the larger iPhone 6 in September 2014. On March 21, 2016, the 5S received a direct replacement with the announcement of the iPhone SE, which incorporated internal hardware similar to the iPhone 6S while retaining the smaller form factor and design of the 5S.
The iPhone 5S is the third iPhone to support five major versions of iOS: 7, 8, 9, 10, and 11 after the iPhone 4S and iPhone 5.