Do you know a music player from fdroid that does this?
So, I'm studying music and while reading and playing the scores I usually get stuck in some parts. Luckily I have the audio of what I'm supposed to play, and here enters my question:
I'd like to put a tag in a specific part of the audio, corresponding to an area of the score that I'm stuck, so that I could easily return and listen and compare with how I'm playing.
With the song playing drag the now playing thing at the bottom up so you can see the playlist. The now playing thing will be on top, now with a three dot menu button, tap it.
Then select Bookmarks.
Then move the progress bar to wherever you want and hit the + sign at the upper right corner. You can even rename each bookmark.
In this screen you can also move between bookmarks with the controls above the progress bar.
Have you considered using a podcast player which can play local files?
They are specifically built with annotations and notes and should help better in this regard. I can't give specific recommendation but you can find a good one on fdroid by searching and using some.