The pinch-to-zoom gesture only works up to a point on any image in Apple’s stock Photos app. But an interesting iOS bug, first noted by iDownloadBlog, allows users to zoom in to their heart’s content.
To take a look, follow these steps.
1. Select any photo in the Photos app.
2. Select edit on the top right corner.
3. Hit the crop button on the bottom left and then rotate the image 90 degrees.
4. Select Done.
You can now zoom in unlimitedly to that specific photo, with some caveats. If you exit the Photos app or select another image, the bug stops working.
I was able to replicate the bug on both an iPhone and iPad running iOS 9.3.2.
View the bug in action
Here’s a video that shows how to replicate the bug. Just to note, it is in Spanish.
I suspect now that the bug has been publicized, Apple will be fixing it soon – either in the next version of iOS, 9.3.3, or iOS 10 which is expected to be officially unveiled in a few weeks at WWDC.