My mom is a pianist and has been using forScore and an iPad for her music for more than a decade. I wouldn’t describe her as a power user (she’s 82 and not too good with computers), but I’ve helped her with the app and it seems every time she has a need, forScore already has that feature.
I’m no musician and don’t own the app, but forScore seems extremely capable to me. It lets you create playlists of songs (“setlists”), edit PDFs (rearrange, crop, rotate, annotate), add metadata to each song (even custom metadata such as your own keywords), sort everything by title, manual sort, newest, etc., and much more.
As one example of its flexibility, my mom has arthritis and has been having trouble playing certain songs. So we added a custom keyword “cantplay” and she tags songs she finds too difficult to play any more, which helps her when she’s putting together a song list (she mainly plays at church these days) as she can easily eliminate those from contention.
BTW, she scans most of her songs from hymnals or piano books herself, using her Brother wireless scanner/printer and Vuescan on the iPad, and imports those into ForScore where she crops, organizes, and adds the metadata. Her biggest problem lately is her memory is failing and if she doesn’t do a particular task regularly, she forgets how to do it and I have to help her.
But all in all, she loves her iPad and can carry hundreds of songs in the space of one songbook. It’s been a game changer for her. She wishes she had that tech 50+ years ago when she really could have used it!