Many "universal" payment cards... well, aren't. They either don't work everywhere or only hold a limited number of cards, which leaves you out of luck when you're trying to add one more loyalty program. Stratos thinks it has this problem licked, though. Its new Bluetooth Connected Card promises "100 percent compatibility" with payment systems in the US, and it can hold an unlimited number of cards that you control through a mobile app. You also shouldn't have to worry about a thief going on a shopping spree if you lose your card, since you can tell it to automatically lock down if it's not close to your phone for a while.