On my phone (Galaxy6), no two photos ever appear next to one another, whether viewing horizontally or vertically. It's always one above another. On my computer, of course, I see the two photos next to each other. Given this, it's much more important to me that the photos line up on the computer, as it is a non-issue on the phone.
Also, both on PC and phone, it is not at all intuitive how to advance pages. I figured out that I need to click on the right-hand image to advance and the left-hand image to go back, but clickable little centered arrows at the far right and left would really help. Also, on my phone I was hoping that simply swiping right, left, up, or down would accomplish that, but it did not.
Hope that helps, at least to give you one data point.