It was about Apple vs the rest of the world, Android included.
The good and bad thing about Apple is their ecosystem. I have a Mac. I want it to work seamlessly with my phone. Prior to the iPhone, I sync my data and backup my stuffs through two mediums, Google and Dropbox. Mainly because they are the ones that support wireless syncing. The good thing about the Mac ecosystem is, everything is designed to run well together. They are not only about the hardware but also the software. This is where fragmented individual developers lose out. Trying to sync Android and Microsoft or Mac is just... compatible, not seamless like Mac.
This was the deal breaker. I wanted the HTC One M8 at first because it was perfect. Such a beautiful design (plus, have you seen the dotcase? WOW) and the M8 also has REFOCUS capabilities on the rear camera. It was the perfect phone IMHO. Then iPhone 6 came out and they didn't have REFOCUS. I thought this was perfect cause I didn't have to think twice. Then I saw the 240FPS ability on the iPhone6. Needless to say, I didn't turn back since then. (the HTC One M8 also has the 120FPS slow-motion video but it just isn't the same as 240. Trust me, I've seen it.)
3. Storage / iPod.
Now when I heard about the 128GB iPhone6, I was thinking it will be an overkill for me. So, I wanted the 64GB. However, upon calculation the 128GB is a lot of extra storage for a little bit of an add on. The thing that finally turned me on the 128GB was the fact that it can and will be an iPod long after it has passed its expiry date. I know after a couple of years I might be getting a new phone and truthfully, I might not fill this 128GB within a couple of years, but the fact that Apple has a large plethora of docks make this thing a perfect iPod.