Thank you for your reply. This is still very much an issue I’m afraid… I just tried it and the upload/editing modal still won’t appear for me when clicking on the “Add to gallery”-button or when I’m trying to “edit” an image in the Gallery field.
Being an older issue I can’t recall what version was used at the time. Right now the site is running ACF Pro 5.2.7 though. Please let me know if I can supply any additional info or anything in order to help out.
Edit: By the way I’m having this issue on iPhone and haven’t tried it out on iPad yet. It was reported to me specifically as a smartphone issue though.