oREC

oREC is a very simple but useful and fun utility for synchronized, multi-track audio creation and collaboration. Here's how it works:
* You record a track.
* Then record another track; the first one plays along as you do, letting you record in sync with it.
* Record as many tracks as you like.
* Color-code them in whatever way suits your needs.
* Use oREC as a personal tool for experimenting with multi-track recordings without any need for a sign in.
* But if you do Sign in with Apple, you can pass the mic to collaborate with any other oREC user whose username you know!
A few important notes:
1. Headphones are necessary for multi-track recording, because audio plays while you are recording with oREC.
2. Wired headphones are necessary for multi-track recording with oREC, because of the latency or "lag" inherent in Bluetooth and other wireless technologies.