There is talk of three years for an iPhone and an Apple Watch, four years for Mac and Apple TV.
To calculate the years of use we assume that this is their first purchase customers: we consider a period of four years for devices MacOS and TVOS, and three years for those iOS and watchOS.
Apple then, an iPhone 6 will be an excellent product until 2018, after which it may always be sold to another person less interested in the power of the hardware or recycle it.
