Are you a dancer who practices with earphones in? If so, we have a solution to your problem. Here’s a dance video recorder that records with your phone's audio with your recording.
You play your song like you normally would — from whatever app, or your own files — and it grabs that audio and puts it right in the video. Even on headphones. So when you watch it back, the music's just there. You don't have to edit anything or line the audio up later.
A few other things it does, since you're here to actually get better:
• Loop a section so you can run the part you keep messing up
• Slow the song down to learn something fast, then speed it back up
• Put two takes side by side to see if you're actually improving
• A countdown before it records, so you can get set
• Everything saved by song, so you can find a take and compare later
That's pretty much it. Record, watch it back, fix the thing, do it again.
iPhone only for now.