Square is not the only company out to replace the cash register of yore. Now PayPal is enticing small merchants with brand-spanking new equipment based on its PayPal Here mobile POS solution.

As a perk to merchants who exchange their old cash register for PayPal's POS product running on an iPad, the company said it will offer free credit and debit card processing, check processing and PayPal processing for the rest of the year.

PayPal is making the same offer to merchants who choose a tablet-based POS solution from one of several participating partners including ShopKeep, Vend, ERPLY, Leaf and NCR Silver.

"At PayPal we've spent a long time listening to small businesses, and retailers of all sizes, and we came to the conclusion that no one company can cater to the needs of all industries," said PayPal President David Marcus. "That's why we have handpicked select partners that are each best-in-class in their respective categories."

The program will begin next month and merchants can sign up for the program through PayPal's Cash for Registers website.

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