Later today, the new version of Apple's mobile operating system, iOS 10, will become available as a free upgrade to iPhone and iPad users. Like every year, millions of Apple users will be eagerly waiting to get their precious devices up to speed, yet some of them are about to be disappointed.
As the technology housed within iPhones and iPads has advanced significantly over the years, so have the demands of the software running them. As a consequence, Apple has to leave some users behind every year. This year it's the iPhone 4s and the second and third iPad generation that didn't make the cut.
As our chart illustrates, the longevity of iPhones has improved over the years though. While the first and second generation of iPhones only received two new iOS versions before being left behind, Apple extended the iPhone’s lifetime from four years for the iPhone 3GS and iPhone 4 to five years for the iPhone 4s, the victim of today’s iOS release.
This chart shows how many major iOS versions past iPhone models have been compatible with.