Thank you for the feedback, I really do appreciate you taking the time to check it out and write out the comment! I'll look at adding a note about total app size in the description, it won't hurt.

As for discoverability / the "your purchase is successful" message, I'm not sure what else I can do, I've set it to free, no ads etc in Google Play. Maybe I need to hit a few more keywords for transcription so it surfaces it more.