Yes, the viewer was definitely a step backwards on the phone. I have switched back to the previous viewer, but modified it so it detects the size of the screen and displays the picture at a reasonable size. It doesn't scale the picture as you resize the screen, so if you want to see a larger version, then...
- close the picture
- resize the window
- open the picture again
The viewer needs an overhaul to work better in the mobile case, but this right now should at least be as good as it was before yesterday's change. The image is resizable by "pinching" and there are no tiny controls.
Let me know if you have any trouble.