I play guitar, bass and thump around on other stringed instruments but my main instrument is tuba and I've spend more time the last couple of years playing in community bands and polka bands than string bands. I have noticed that in the on line community of horn players it's popular to use some kind of phone app to record yourself playing various parts then sync it together with a split screen to play a duet or even a quartet. I myself have not tried this. I don't think I've seen guitar players doing this. Plenty of people play bass, drums and guitar. Looks like lots of possibility. Why? some type of different personality type?