IPhone 7 lock that prevents individuals from attempting to replace the home button on their own. Users are now required to go to an Apple Store to have repairs done, with "recalibration" of the button being necessary. This is a step further than Apple went with iPhone 5S, 6 and 6S, where only Touch ID functionality would get disabled but the "return-to-home" functionality still worked. Some iPhone 7 devices with the model numbers A1660, A1779 and A1780 suffer from a problem where they show a "No service" message even when cellular reception is available. Apple will repair those devices for free within
IPhone 4 supports up to iOS 7, released in September 2013. Due to the relatively aged hardware of the iPhone 4, certain features available on newer iPhone models are not available on the device; as of iOS 7, they include Siri, 3D maps and turn-by-turn navigation, AirDrop, AirPlay mirroring, live camera filters, panorama mode and certain visual effects introduced by iOS 7, such as the blurring of translucent interface elements, the parallax effect on the home screen, and live wallpapers. While still subject to the same limitations, iOS 7.1 did bring some slight performance improvements to the operating system on the iPhone