[mstade]

It's worth mentioning though that there's often not a 100% feature parity between iOS versions on different devices, typically because of hardware changes. These even applies to devices of the same generation, e.g. iPhone 7 and iPhone 7 Plus have different camera features since the latter has two cameras and the former just has one.

The differences between feature sets on different generations is less and less it seems though. If I recall correctly, the differences between the iPhone 3G and iPhone 4 was bigger than for instance iPhone 6 and iPhone 7. If I weren't such a sucker for new and shiny things, I'd probably buy an iPhone SE today.