LoopPay has begun shipping its iPhone case, which can be used to make credit card payments at any magnetic swipe terminal. Instead of using near-field communications or special software, Loop's ChargeCase creates a magnetic field that emulates the data stored on a credit card and can be read by any point-of-sale terminal its held up against.

Last year, I reviewed Loop's fob, and was actually quite impressed with how simple it was to use. The ChargeCase is basically the fob in a different form factor designed to fit around an iPhone 5 or 5s.

It connects to the iPhone through Bluetooth, instead of through the audio jack like the fob, but otherwise the principle is the same. Pressing a button on the side of case causes it to emit its magnetic field transferring your credit card data to the point of sale terminal, just as if you had swiped your physical card. The case works independently of the phone, so you can make a payment if the Loop app isn't active or even if the phone is off.

The Loop iPhone ChargeCase and fob

The Loop iPhone ChargeCase and fob (source: LoopPay)

The case does offer some advantages over the fob, though. First, since it's in constant connection with app, it's much easier to switch between cards, and it keeps a running tally of transactions you've made. It won't record any details of about the amount or location of the transaction, though Loop founder and CEO Will Graylin told me that feature is coming.

Second, the ChargeCase has a built-in battery pack, which Loop says will boost an iPhone charge by 60 percent. The ChargeCase keeps a power reserve so users can continue making payments even when both the iPhone and the battery pack are drained.

Loop began offering the ChargeCase via a Kickstarter campaign in November. Those initial investors have received their cases and have begun testing the device, Graylin said. Starting today, Loop is making the ChargeCase available to the general public on its website for $99 and will start shipping it to customers who pre-ordered the device.