After about 8 years using Android smartphones, it has become my go to mobile operating system. Android just works for me, in a way iOS just can't compete. Not that iOS is bad, its just that it simply doesn't works how I want it to, and Android fits with how I use my smartphone a lot better.
Add to it, that with each new Android version it just keeps getting better for my use case, moving to iOS is less appealing. There is also the fact that Android OEM keep releasing better smartphones each year, it does feel like an upgrade each time I make the choice to get a new one.
Most importantly, the mid-range Android smartphones give a great value in the hardware the have. They might not have the greatest, and latest, tech in them, but they work great for the use I've for my smartphone. They actually find they give me more for the cost they have.
The fact that there are several options with in the Android ecosystem, making OEM having to compete among themselves, makes for appealing smartphones and choose the one that better fits my needs with some extra things that I want to have at hand. In most cases, I'm able to find the smartphone that gives me that extra without going out of budget, or for just for a little more if I can.
Android just works, and it keeps getting better.