I haven't really looked into this much so I'm mainly creating this as a to-do list item for the future.
I recently picked up a pinephone and have it running postmarketOS. There's some functional spotify clients for the pinephone in general, but it would be cool if we could have aarch64 alpine as a package out of the box. There's already an x86 package so this shouldn't take an insane amount of work.