When Evan Ozmat, a Ph.D. student in psychology at the University at Albany, first began counseling undergraduates about HIV and substance abuse, he expected to hear about their health issues. Instead, he heard about problem gambling.

“Since the beginning of the project three years ago, students have brought up, unprompted, gambling,” Ozmat says. “We started asking about it in every appointment and everyone has something to say. It’s everywhere.”

The majority of the gambling takes place on mobile phones, Ozmat says, largely—although not exclusively—on sports betting apps. Served up to students through ubiquitous ads that offer promises of “free” bets and easy wins, the apps sink their hooks deep into students, leading them to spend their financial aid money,…