Okay... erm. Forgot the part where I'm too new to post links in messages. I've put the dropbox link in my profile page under Biography instead.
Thanks for sending, Bernard ;)
Quick update: Jumping ship. This phone is being returned and I'm grabbing a google pixel xl - much cheaper, same general age, less bloatware, easier to root, and better camera from all indications.
Does not appear to work on a US Sprint S3 running stock rooted 4.1.2 though I figured it was a long shot since to my knowledge this model doesn't support charger tests. Good work on your app though! I love the simplicity and the lack of permission...