nostr:npub1tgkmcmrd6aqrdzj3u65r0wvwqac7z4xnmcu9xmat4y3s0scqqrws464t9m I never tried an Android-based reader -- but I'll throw PocketBook out as worth a look. Has a minimal Linux-based OS and you can use entirely without any account or internet connection. Supports many formats, so good for DRM-free collection. New ones have optional Adobe DRM support (Adobe account required). It is also very easy to set up KoReader, which I prefer to native reader. I doubt it would check the music/email boxes well, however.