The specific calendar day upon which Apple made available the fifth major version of its mobile operating system, iOS, is a point of historical significance for users of iPhones, iPads, and iPod Touches. It marked a key upgrade cycle for those devices.
The availability of this iteration brought considerable improvements to user experience, including the introduction of features like Notification Center, iMessage, and iCloud integration. These enhancements represented substantial advancements in mobile technology accessibility and functionality at the time, shaping subsequent software developments.