LAS VEGAS ( KLAS ) – If you haven’t been .. you really gotta go to The Mob Museum.

It has so many cool exhibits – – and they’re always trying something new.

They’ve also been incorporating more technology… like the app they just debuted this week. It’s free for Apple and Android users.

It has an interactive map of all four floors of the museum.

It also has ‘missions’ — so you search the museum for answers to complete the mission.

The app also lists the hot spots for selfies.

And it even has a feature to find your ”doppel-gangsta.”

The Good Day Las Vegas crew gave it test.

John Langeler’s “doppelgangster” is – – Liberace!

For Alex Backus it’s Daisy Simpson, who was a fearless undercover prohibition agent.

For Sherry Swensk, how about Hedda Hopper who played Karen Lee in the movie “The Racketeer.”

The app tell Nate Tannenbaum he’s Arnold Rothstein, a gambler who was accused of “fixing” baseball’s 1919 World Series.

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