He, I test your plugin for 2 days and found a few problems:
When I click on an image, then the label appears in the middle of the image
When I move an image a little higher, then it behaves as I press Share button
When I zoom an image then everything enlarges (including buttons).
When I zoom an image and move it, then it jumps on the display – usually it jumps to bottom of the display.
I made this test on https://codeasily.com/portfolio-item/gmedia-phantom/ and on my testing page (clean WP, only basic settings WP) http://www.kps.cz/2wp/test-phantom/ , The 3. and 4. problem is only on my page as your gallery is not possible to zoom.
2 phones – Android 5 MIUI and 4.4.