App wont even open

I bought this app a couple of weeks ago. It was a green icon at first but since it updated it is now purple. It will not open anymore. When I click it my screen glitches and it shuts down. Im very upset about paying for this app. Not only is it a waste of money but I was utilizing it for my upcoming board exams. Do not buy this app unless they fix the glitch. I want my money back.

UNE DH student about AndyRDH Board Review for NBDHE