With phones, watches, apps and cryptocurrency, the days of “cash or credit” are long in the past. Retailers continue to seek competitive advantage by adding diverse ways to pay, including applications like Venmo or PayPal, allowing “by now pay later” plans like Klarna, or even accepting cryptocurrency, according the National Retail Federation.

“One concern merchants may have with bitcoin transactions is the price volatility,” says Joowon Park, an assistant professor of marketing at the David Eccles School of Business. “What if I get paid in bitcoin, and then bitcoin price crashes the next day?”

Read more about the rise of alternate payment methods – and Park’s take on them –  at the National Retail Federation.