Posted: Friday, 21 March 2014 7:48AM

Billy Joel Duets with Jimmy Fallon, an iPad on "The Tonight Show"

Lloyd Bishop/NBC(NEW YORK) -- On Thursday's The Tonight Show Starring Jimmy Fallon, Fallon welcomed Billy Joel ahead of his concert at Madison Square Garden Friday night, part of the legendary performer's residency there.

"It's a great place," Joel said of the Garden. "Best audience, New York. The building is built on when you're on stage...the crowd is rocking, the stage goes up and down like an earthquake."

The pair collaborated first on a doo-wop-tinged version of The Tokens' "The Lion Sleeps Tonight" -- thanks to an iPad app that allows users to overlay their own voices.

Joel and Fallon later jammed to Joel's hit "You May Be Right," with both men taking turns on vocals and singing together on the chorus.

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