Mobile payment company Buck is looking to disrupt an already disruptive space. It announced the launch of its new "dongle-free payment service" that targets the same small merchants serviced by mobile point-of-sale providers such as Square and Intuit GoPayment.

"We're like Square, without the dongle," said Buck CEO Andy Kleitsch.

The new service, called Buck Mobile Invoice, lets merchants send invoices to any mobile phone and instantly receive credit card payment, the company said. And it gives repeat customers the ability to pay their bills from their mobile devices with a single tap.

"Our service is a game-changer for businesses sending paper bills" says Andy Kleitsch, CEO of Buck. "Many small and medium businesses spend hours stuffing and licking envelopes, mailing them, and waiting weeks to receive payment. With Buck Mobile Invoice, merchants send invoices from the job site, and receive payments instantly. We've shortened the invoicing process from weeks to minutes."

The merchant uses a mobile device or PC to enter the customer's invoice amount, purchase description and mobile phone number. The service then sends a text message to the customer's phone with a link to a mobile optimized payment page where the customer can enter payment information.

According to Buck, the service is available to businesses that hold merchant accounts with a number of payment providers, including Authorize.Net, Stripe, First Data, Chase Paymentech, PayPal and CyberSource.

A video from Buck demonstrating the new service is below:

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