Apple announced iOS 7 on June 10, 2013 at its annual Apple Worldwide Developers Conference (WWDC) event, and it was released to the public on September 18, 2013 alongside the iPhone 5C and iPhone 5S. With this release, Apple dropped support for the iPhone 3GS (due to hardware limitations) and the iPod Touch (4th generation) (due to performance issues). iOS 7 has limited support on the iPad 2 and the iPhone 4 since they do not support Siri. However, other devices from the iPhone 4S onwards, iPod Touch (5th generation) onwards, the iPad 3 onwards, and the iPad Mini (1st generation) onwards were fully supported. The release of iOS 7.0.3 brought support for the iPad Air and iPad Mini 2. iOS 7.1.2 was the final release on the iPhone 4. It became unsupported on 23 November 2018.