WSJ: Apple tells its supply chain to prepare for an initial build of 85 million-90 million iPhone 6s units52
It was the increase in iPhone screen size from the 4-inches used on the Apple iPhone 5s, Apple iPhone 5c and Apple iPhone 5 that brought out heavy demand for the new handsets. During the 2014 holiday quarter, Apple sold a record 74.5 million iPhones.
Apple strongly believes that it has a game changing feature to offer on the next-generation iPhones with Force Touch. Currently used on the Apple Watch, Force Touch allows the device to differentiate between a hard tap and a light tap on the screen. Other rumored changes include the use of Series 7000 aluminum, also employed by Apple's timepiece, which would prevent the new units from bending. The rear camera is also believed to be getting a bump from 8MP to 12MP. The iPhone 6s and iPhone 6s Plus will be powered by the new A9 chip and will have 2GB of RAM inside. A new Rose Gold color is expected to be offered for the next-gen iPhone models.
The latest rumor has the Apple iPhone 6s and Apple iPhone 6s Plus both becoming official on September 11th. Both models could then be released on September 18th.