IPhone 6S iPhone 6S and 6S Plus. On March 31, 2017, the iPhone 6S and 6S Plus were released in Indonesia alongside the iPhone 7 and 7 Plus, following Apple's research and development investment in the country. The iPhone 6S, iPhone 6S Plus, and iPhone SE were the last iPhone models to feature a standard 3.5 mm stereo headphone jack. The iPhone 6S is nearly identical in design to the iPhone 6. In response to the "bendgate" design flaws of the previous model, changes were made to improve the durability of the chassis: the 6S was constructed from a stronger, 7000 series
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