NEW YORK--(BUSINESS WIRE)--Which Wich, the award-winning, national, fast-casual sandwich brand, today announced its partnership with Olo, the leading provider of online and mobile ordering solutions for the restaurant industry. The partnership debuts a new mobile app and digital ordering program, giving loyal fans the option of ordering and customizing their favorite hand-crafted superior sandwiches online via web and smartphone platforms at order.whichwich.com, Apple’s App Store, and Google Pl