Someone here posted that Apple iPhone is a premium brand and therefore it is as much a status symbol as it is a very functional and reliable phone.
Style and cachet is very important for many you only have to witness the sales of various euro-brand (allegedly) luxury cars to the aussie middle class to witness how perceived style and cachet takes precedence over necessity and reliability.
IMO Apple will always seek to occupy the luxury segment and other than the short-lived 5C plastic model iPhones, they will not provide a budget model, they will likely never again lead the everyday smartphone market but they continue to work to dominate the luxury smartphone market.
Fortunately for apple users they get a very durable & reliable device that works seamlessly with most other devices whether they be apple or windows, and they get a relatively safe OS that is supported for the life of the phone the software access to is regulated only by Apple which reduces instances of malware.
Also if you use android, google is watching you to make their advertising highly tailored to you and if you buy Chinese brands like Huawei some of these brands are very close to the Chinese central government and you may well be sharing info with it.