If you are a retail store are you accepting EMV cards yet? As of October 1, 2015 you are supposed to be prepared with new equipment to accept EMV credit cards (those ones with a chip in them).
Two words: Liability Shift. Right now if you accept a fraudulent credit card, it is the bank who eats the cost. Starting in October of 2015, if someone pays with a fraudulent chip card and you didn't have the appropriate card reader, your business will be on the hook. So if someone buys a $60 meal with a fake card, and you still have the old machine, the bank will not be paying you that money.
Square and Paypal have reasonably priced readers that can be attached to several different devices. Check out the links below:
https://squareup.com/shop/reader
https://squareup.com/contactless-chip-reader
https://www.paypal.com/webapps/mpp/emv
https://squareup.com/townsquare/emv/
http://www.washingtonpost.com/news/get-there/wp/2015/09/30/get-ready-to-dip-not-swipe-your-credit-cards/
http://www.usatoday.com/story/money/business/2015/10/01/chip-credit-debit-card-readers-october-1/73140516/
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