SALT LAKE CITY - David Morales was on a Greyhound bus near Las Cruces, N.M., when Border Patrol agents stopped the bus for a routine check. Morales, 21, rose up and informed his fellow passengers of their rights. That, he says, landed him in detention for nine hours before immigration agents decided to cut him loose. The experience, he says, was his inspiration for developing an app to inform undocumented people of their rights in a wide array of scenarios ranging from traffic stops by city police officers to a workplace raid by Immigration and Customs Enforcement agents. "I can't...