Partial screen zoom

[ctechols]

The android app "Perfect Viewer" had a nice feature for reading comics on a small screen. If you wanted to zoom in on a speech bubble, you could long press the screen on the bubble. The app would create a borderless window that zooms in the region around the long-pressed point. That borderless window would be rendered on a portion of the screen that is not obscured by your finger.

For example, suppose there's a speech bubble or tiny panel in the upper right quadrant of the screen. You'd long press that area, then a window would pop up in the lower left corner that zooms in on (perhaps) the region that is 25% by 25% of the image that surrounds the long press point. As you drag your finger around, the zoomed window is updated to reflect the new point. If you drag your finger near the zoomed window, it is repositioned.

I always felt this was more convenient to use than pinch-to-zoom, especially for more modern comics with complex page layouts and unconventional panel flows.