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 time as Apple's flagship iPhone model at fifteen months, and had the longest lifespan of any iPhone ever produced, spanning close to four years and available in some developing countries until early 2015. Although the succeeding 4S was announced in October 2011, the 4 continued to be sold as a midrange model until September 2012, and thereafter as the entry-level offering in Apple's lineup until September 2013 with the announcement of the iPhone 5S/iPhone 5C. Before the official unveiling of the iPhone 4 on June 7, 2010, two prototypes were brought to the attention of the media, breaching Apple's normally