[jusmee]

Seems to work well and I like the numbers. My preference is that pushing fingers together makes the image smaller etc. Don't recall how it works now but that seems to be how most apps work. It should be consistent with other apps to avoid confusion.

User choices in preferences is also a good idea.

Yes, giving the user a choice is best.

The reason I like it better the other way, is because of the very visible rectangle that moves in response to your fingers. It feels like you are controlling the size of that rectangle when you pinch-zoom, so when the rectangle moves the opposite way, it feels wrong to me, despite the result being that the page gets larger as you pinch your fingers together, since that happens after the fact, not as you are moving your fingers.