Apple has made available the latest iOS 7 OS to existing Apple iPhone 4 handsets and later, iPad 2 tablets and later, and iPod touch (5th generation) devices.
iOS 6 and earlier users can upgrade over-the-air by navigating to "Software Update" in the "General" section of the device's settings. Thee update is large so you'd better connect via a Wi-Fi connection.
Alternatively, Windows and Mac users can connect their compatible iPhones, iPads, and iPod touches to the latest version of iTunes 11.1 and upgrade by selecting the "Check for Upgrade" button in their device's summary window.
Or, users can download the software bundle files from Apple's website for offline installations.
iOS 7 includes many new features, including a new bright and colorful user interface as well as a number of business-ready features.