Hopefully someone here knows of any iPad app (any app is ok! I'll buy it!) that has a way that I can sing through a live microphone and then when I hold down a button (on a midi controller or the iPad screen) it will take a sample of the live mic input for as long as I hold the button and then echo (repeat gradually softer and softer) while I continue to sing.
So this is basically a quick way of layering vocals. I don't have any experience with loopers and such, but I'm asking this Q as a way to begin learning. Any relevant terminology would be appreciated!