Great setup, but it doesn’t work and I lose all my notes

I use this for active editing in class (I’m in med school and have class mostly 9-5). I write a LOT of notes so I updated to Pro (it won’t let me write a review for the pro and I don’t know why).

This app started as a great resource, but now it has been slowly devovling.
This app started crashing and I lost all the notes I didn’t save. Now when it crashes I lose all notes, even the ones I saved from before. I am so frustrated that I want to throw my computer against the wall and erase all memory of having this app. Thanks for helping me lose hours of work. I have to get back to re-writing all my annotations now.

Pros:
-It’s easy to write, draw, circle, and highlight.
-It’s easy to use the app as a means to organize and open all your PDFs.

Cons:
-Sometimes there is Lag in the GUI that stays on the screen until you overlap it with another GUI
-It crashes. An absurd amount.
-I lost all my work.
-Even though I purchased the Pro, it says I have the Free Edition

If the theory of the app was not so great, I would give it a 1/5. The app functionality is a 0/5, but the awesome theory is great.
I wish I could get my money back.

MedSchooOrBust about PDF Reader X - Edit Adobe PDF, v1.20