Much like many of the iPhone users when you asked the converse question, it's not so much that something is stopping me, but that I have no interest in it. I don't see any benefits that I care about, and it would cost time and money to switch.

Let's pretend for a moment that I did have some desire to switch, perhaps due to some new hardware from Apple or changes to Android I found unpalatable. Here are some things I'd consider major barriers:

• Sideloading - I want to install stuff without permission from the hardware or OS vendor. Maybe I'll even write a niche app without asking permission.
• Administrative access - I have root on my Android phone, and I didn't have to fight it to gain root (I know that's not true of every device). If I don't have root or can't get it easily, it's not really mine.

That's... basically it, but those are big things and Apple's position on them is so opposite mine that they're risking severe sanctions from the EU to comply with the EU's sideloading regulations in the most useless way they can.