How safe are mobile payments?

For some consumers, paying at the checkout line becomes a lot simpler when they can forgo the plastic card and pay with their phone. Mobile payment applications like the Isis Mobile Wallet, Google Wallet, Square, and LevelUp turn your cell phone into a payment source: Just store your debit card or credit card information on the phone and scan the device at checkout. "Consumers like the convenience factor," says Sarah Jane Hughes, a commercial law professor at Indiana University. But is this new form of payment safe?