The main advantage ios has over Android is its lack of support for virtualization (like java). This makes their apps much less resource hungry, faster, and the phone does not slow down as much over time. Given the fact that idiotic apps like Instagram and Facebook need supercomputers to run on Android the difference for the end user is a huge gulf performancewise. It must be a nightmare for developers though.
For people who know what they are doing it is very easy to maintain the software health on android and keep it running fast over time. If you don't though usage of apps like the ones mentioned above will make it run like a commodore in months.
Also nukes