iPhone or Android, whichever OS want.
I prefer IOS because the operating systems are much less fragmented, in my opinion, than Android. So many different versions of Android out there. But, IOS is certainly not without its issues or faults. I do believe the apps are better overall with iOS, because software makers seem to make more money with iOS apps, and they are easier to support them.
I also think the high end Android phones keep making strides and do somethings better than the iPhone.
A good smart phone is a serious business tool for people today.
But to me, the worst investment is a cheap or free Android phone. The market is flooded with them. Some people cannot resist the "free" temptation. But the carriers made MUCH more money from giving you a free phone that costs them $50 than giving you a subsidy of $400 of a high end phone.
They changed the way they do it, But they still make much more off selling a cheap Android than a high end phone
The free Android phones are almost bearable if you really don't use apps or data on your phone, but then why are you paying for a data plan?
I don't know anyone who uses a smart phone seriously that uses a cheap one. Some have 2 gig of memory, with half being used up by bloatware. They are basically for kids and senior citizens, both of which don't really need a smart phone
My iPhone works well, I keep it in great condition with a case, and can usually sell the old one when I upgrade. So would I spend $749 on a smart phone? I doubt it. The last one I bought was $969(7 plus, 256g), I can't see myself going to a cheaper model any time soon. I doubt the new one will be less expensive.