Starbucks turns to a celebrity CEO as it struggles to define itself for an era of mobile orders [Video]

To Howard Schultz, the chaos he observed at a Starbucks in Chicago one recent morning summed up the troubles of the company he long led as chairman and CEO.

Commuters tumbled off trains and into a Starbucks store to pick up the orders they had placed on their cellphones. Drinks weren’t ready when the mobile app said they would be. Customers couldn’t tell which beverage was theirs.

“Everyone shows up and all of a sudden we’ve got a mosh pit,” Schultz said during a June episode of the podcast “Acquired.” “That’s not Starbucks.”

Fifty-three years after its founding, the Seattle coffee giant is unhappy with what it’s become – and trying to figure out how to meet customers’ changing needs without losing its coffeehouse roots. To recapture what once made it special — and turn around sagging sales — Starbucks is turning to Brian Niccol, an experienced marketer who previously led Taco Bell and Chipotle.

Niccol takes over …