A mixtape in Audionix is a cassette you assemble yourself. You pick songs from anywhere in your library, across folders and albums, and they end up together on one tape.
The slow, good way
Songs go on one at a time, and that's the point. You listen, you decide, you add the next one. It's slower than dragging a hundred tracks into a playlist, and the tapes come out better for it.
Label it
You name the tape and label it the way you want. A tape called Rainy Tuesday tells you more than a playlist with a date on it. In cassette view that label sits right on the front.
Mixtape or queue?
A mixtape sticks around. It's a thing in your library that you can insert whenever you like. The queue is for tonight. If you're lining up a one-off run of albums, use the queue. If you're making something you'll want again, make a tape.
Mixtapes live on your phone like everything else. Nothing is uploaded, and there's no account to save them to.