As further proof that the mobile POS market is becoming completely saturated, daily deal site Groupon is reportedly looking at entering the mobile point of sale market, introducing its own credit card reader/app combo to let small businesses accept credit and debit cards. VentureBeat originally broke the story and said Groupon's competitive offer would include rates far below those charged by companies like Square, PayPal, Intuit and VeriFone.

According to VentureBeat, Groupon will charge a 1.8 percent transaction fee and 15 cents per transaction. (Amex transactions would be charged at 2.7 percent). That compares with Square's 2.75 percent and the 2.7 percent charged by PayPal Here and VeriFone Sail.

A Reuters report said the new Groupon service will eschew the dongles provided by competitive services and use a "wrap-around" reader for iPod Touch devices to capture card data.

Groupon refused to provide any information on the new service, but it's an interesting move for the company, if true. Groupon purchased FeeFighters earlier this year, a company that helps merchants search for the best deal in merchant services. Additionally, the company has been rolling out services like merchant rewards that go beyond its group buying and daily deal roots.

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