Credit cards that offer rewards are great, but if you're like most Americans and have a wallet full of credit cards, you may have a difficult time making those cards work for you and getting the most possible rewards from them. Now with the Wallaby Card, you can combine your credit cards to simplify and get the most value from them.

The Wallaby Card is a service from Wallaby Financial, a company that's come from the Los Angeles-based MuckerLab startup accelerator program, that combines your credit cards into one single credit card that also has a personal digital wallet attached to it. Whenever you make a purchase with the Wallaby Card, the card's system examines the credit cards linked to it and the type of purchase you're making, and it charges the card that will give you the best rewards. You don't have to do anything special. The card acts like a normal credit card that you swipe and sign a receipt.

This works particularly for limited-time rewards, such as bonus cash back or multiple points offers. If one of your cards is offering extra cash back for grocery purchases for a few months, the Wallaby Card will recognize when you're buying groceries and will direct the transaction to the card that has the special offer.

The Wallaby card is not a standard credit or debit card, which means that the company doesn't make a hard credit check on your account. The card itself doesn't have a credit line connected with it, so it can't affect your credit score. It is, however, not a replacement for your credit card accounts. You do still have to pay each credit card provider whose card you're using.

Users do have some control over the system, if they don't want Wallaby to automatically manage the process. By creating a personal profile, you can allocate certain percentages of spending to specific cards, and you can even tell the system to allot certain item categories to a specific card. You can also tell Wallaby what your goals are in terms of building rewards, and the system will work to help you meet your rewards goals.

Wallaby also has a social media element that automatically checks you in to Foursquare or Facebook, and it can broadcast Facebook "likes" and tweets about transactions to your friends. You can also manage your account on a mobile phone, where you can add and remove credit cards, change preferences, find rewards and see real-time updates on the amount of savings you've accumulated.

"Wallaby is the first service that brings together a new combination of a flexible, cloud-based wallet and an intelligent, connected physical credit card that can be used at any location," said Matthew Goldman, founder and CEO of Wallaby, in a statement. "We know from primary research that 90 percent of consumers carry rewards cards and 70 percent of them agree that credit card rewards programs are confusing. We are making it easy for people to earn the most rewards by channeling spending toward the best card for each transaction, making sure each consumer gets the most from their credit card annual fees. What makes this really great is that we do this behind the scenes, with zero effort or change in normal behavior required by the user."

The Wallaby Card costs $50 a year, although it has an introductory six-month free usage period. The card is also currently in its beta version, so Wallaby is offering a free lifetime membership to the first 1,000 customers who register for the service. The next 5,000 registrants who sign up for the Wallaby wait list will receive a free Wallaby Card for twelve months.