WP App v5.5 on iPhone 6 running iOS 8.4.1.
Take picture with built in camera app.
View and edit picture with built in iOS Photos app using crop function to crop.
Upload cropped image using WP app.
View and edit picture again using Photos app, revert picture to original size, crop again to another area of image.
Upload re-cropped image using WP app.
Rinse and repeat once more for a total of 3 uploaded images.
Mine as well uploads and appends and increments a number to duplicate file-names.
I can’t give you an admin login so if this isn’t enough information to reproduce, I can try to find the bug myself and feed back the fix.