Hi Product Hunt, I make Note Names.

You open a PDF or point your iPhone at a page in a book, and every note gets its letter, inside the notehead or as small tags above and below the staff. It follows the key signature, so an F in G major shows as F♯. It handles alto and tenor clef too, which matters if you play viola or cello.

Reading is done on your phone. Your music isn't uploaded anywhere, and there's no account.

The part I care about most is "How many letters". Every note labelled is a crutch, so you can step it down: fewer letters, then just landmark notes, then only ledger lines, then none. Each piece remembers its own setting, so a piece you've learned can go bare while a new one keeps its letters.

Printing came from a review. Someone asked to take the lettered page to their piano, so now any piece prints or saves as a PDF, free.

It's free to try: 30 classical pieces checked by hand note by note (Für Elise, Turkish March, Bach's Minuet in G among them), plus one piece of your own. Unlimited imports is US$9.99 once. No subscription.

Two things it doesn't do yet: solfège (Do Re Mi) and playback. If either would make you use it, tell me in the comments.

One thing to clear up: there's another app on the App Store also called "Note Names". It isn't mine. Mine is Note Names: Read Sheet Music.