The feature arguments between the two platforms have largely been settled by both copying whatever worked. The differences that remain are structural.
Where iOS is ahead
Software support duration, and the proportion of devices actually running the current version. Android update commitments have improved substantially and delivery still varies by manufacturer.
Resale value, which is consistently higher and is a real cost difference over a few years.
Ecosystem integration, if you have other Apple devices. Handoff between them is genuinely seamless in a way cross-platform alternatives are not.
Where Android is ahead
Choice, at every price point. There is no cheap iPhone in the sense there are cheap Android phones that work well.
Flexibility – default apps, file access, sideloading, customisation. This matters a great deal to a minority and not at all to most people.
Hardware variety, including formats Apple does not make.
Where they are equivalent
Camera quality at the top end. App availability for anything mainstream. Security, for an ordinary user who keeps the phone updated.
The switching cost
The real reason most people stay is not the platform. It is purchased apps, messaging history, ecosystem accessories, and the shared arrangements within a family.
That cost is genuine and it is the strongest argument for staying wherever you are.
The honest advice
If you are happy, the other platform will not make you happier. If you are switching, do it when you would be buying a phone anyway, and expect a few weeks of friction.