I'm a great big fat android fanboy - but I'm this is why Android is bad.
Apple (for better or worse) to seem to support their hardware: https://en.wikipedia.org/wiki/List_of_iOS_devices#Highest_version_of_iOS_supported
Or at least if you're a 4S or beyond owner, they seem to have you covered.
With them you're getting updates for a 4 year old device, but in world of premium android you seem to get a "gentleman's agreement" on 2 years, and then you're on your own.
Still, not quite as bad as it seems for Android - Google with "play services" seem to have been incrementally pulling more updates under their control, but it's still a bit half-arsed.
Bit that always bemuses me though, is why they don't just embrace the Windows PC model (or probably more accurately the Windows PC laptop model) - with a Linux twist.
There's less variance in phone hardware than there is on your average PC - buggered if I can't think of a reason you can't roll a "Google Play Installer" that checks components, and installs the relevant drivers.
Has anybody actually bought an Android phone, due to the OS modifications in the last few years?