Square is an app that allows you to take credit cards on your iPhone. It's become a pretty handy technology for us at conventions, but I wonder if this might be the next step...especially since Baltimore is practically the panhandling capital of the East Coast.
inb4 folks start bashing the homeless. Please don't. This is a comment on the technology, NOT panhandling. Personally, if I have it I never hesitate to give money to those in need.
Personally, if someone offered for me to pay for something on an APP on their computer, I wouldn't trust it. I'd be too worried about identity/credit card theft.