I have owned a couple iPhones now and for each model I have owned I have a Mophie Juice Pack to keep its battery running longer. My favorite is the thin Juice Pack Air for my 3GS iPhone. Mophie is set to unveil another hardware accessory for the iPhone that looks a lot like the Juice Pack Air that is actually a credit card reader.
The device is apparently called simply enough the Credit Card Reader and is a much more integrated looking device than that ugly Square mobile payment accessory that plugs into the headphone jack. The device will work with a third party app that actually handles the processing.
As interesting as these card readers are, it worries me how easy it is becoming for nefarious types to steal our credit card data. I had my card info stolen recently from a local business and the crook used the number to order ladies clothes online. I get a little twinge each time the waiter at a restaurant leaves with my card and this sort of tech just makes that twinge worse for me.