This is my first iPhone, and second Apple product I've ever had. The first being an iPod back in 2003. I'm coming from an Galaxy S3, that I loved customizing, rooting, flashing custom roms, etc. Eventually I grew bored of Android, not because it's not a great OS, but because I wanted something different. So I grabbed an iPhone 6, and I love it very much. I'm in no way a fanboy, and in two years I'll be back on the fence to see what my options are.
So, my top reasons I love my first iPhone:
1. Great games (and apps). I love gaming, especially board gaming and retro gaming. And the AppStore has a ton of these in much higher quality than the android store.
2. Design. The minimalist, and high quality build of the phone itself, and the UI in IOS is something I really appreciate.
3. Hardware: Screen, audio, speaker, camera, cpu. Are all very good, if not great. Sometimes other phones get a few things right, Apple makes it a point to make everything come together really well.
4. Great set of built in apps that I don't have to upgrade. It seemed like for android, I was constantly replacing their apps with better 3rd party apps. It was great having the choice, but what I ended up with was a bunch a really good but disjointed apps. I like a lot of the built in Apple apps, and don't feel like I need to go find the best browser or whatever. And in the end, the experience seems more fluid, because the UI's have a common theme.
Anyway, just my opinions, I'm loving this new phone and the experience I've been having.