These swipe-free cards are generally the same as any other credit card. However, because they are 'new', not all vendors currently use them as their credit card machines cannot read them.
Comparing contactless credit cards to find the best fit for you calls for looking at APR, when and how APR can change, rewards, finance charges and length of grace period.
APR (Annual Percentage Rate) is almost always the first item that persons looking a credit card, regardless of the type of card, check. The APR tells how much you have to pay in addition to what you have spent. Other charges are also applied to credit cards that can really add up at the end of the day, especially those hidden charges that are not so obvious to the average credit card holder.
Also, it is important to know under what circumstances APR can change, as a low rate APR can increase. This can be problematic if you carry a monthly balance on your card.
If you are a big spender, getting a credit card that offers rewards should factor into your card comparison benchmark. Looking at the types of rewards is also important, since a commuter would probably like a gas reward, while a frequent traveler may prefer a card that gives miles.
Late charges can be quite hefty, so compare the length of grace period before making that final decision. Remember that carrying a balance beyond the allotted grace period can result in additional charges, plus an increase in the cards APR.