The Mobile Phone as a Credit Card POS

After the much talked-about Square service, which turns any iPhone into a point-of-sale (POS) terminal for swiping credit cards, comes Card.io, which promises to do the same without the need to attach any additional hardware. Card.io uses the phone's built-in camera plus its pattern recognition software to read the card details. Hmmm... I don't know, but this sounds to me like a solution looking for a problem.