This is a sample transaction using Square to accept a credit card payment
If you want the simplest, easiest way to accept credit card payments, now you have an option. Square (http://www.squareup.com) offers a free credit card reader for iPhones, iPads, and Android smartphones and tablets. Yes, free. All you need is a smartphone or tablet and a bank account.
Square started in 2009 when a glass blower named Jim McKelvey was having trouble making sales because he couldn’t accept credit cards. He mentioned this to his friend, Jack Dorsey (one of the founders of Twitter) and with the help of Tristan O’Tierney, Square was born.
I had to try it. It sounded so easy, and I’d been wanting to be able to take credit cards. In this economy, that can mean the difference between being paid now and being paid in 90+ days from some clients. Easy for them, easy for me, everyone wins.
I signed up for an account at squareup.com. It was easy, took a few minutes. I then downloaded the free app from the Android Market (I’m currently rocking an HTC Thunderbolt) and waited for the Square reader to arrive. That takes about two weeks, but it’s 100% free. In the mean time, I could have hand keyed in any transactions. The caveats with that method are a) the charges are higher, at 3.15% instead of 2.75% for swipes and b) if you charge more than $1000 in a seven day period by keying it in, they may hold the funds for up to 30 days as a fraud precaution. 
The reader, larger than actual size!
I had nothing to charge at the time, so I waited. It arrived, and I fortunately hav a couple of things to charge. Today was my first charge. I plugged in the Square reader, fired up the Square app, signed in and entered the charge. My client was able to swipe the card, sign with his finger (a stylus might be a handy thing to carry for this, but a finger worked fine), and enter his contact info. He swiped it and immediately was both charged and his phone chimed to let him know he already had the receipt. It even records the location and shows it on a map to both him and to me. If it’s ever used fraudulently, you’ll know where and when.
I was immediately alerted that I had received a payment. That payment automatically transfers, sans the Square charge of 2.75%, within 12-36 hours of payment directly to my bank account. I have to do nothing.
This system works so well, I have to applaud the company. I’m impressed. If you have a small business (even a side business) and don’t currently take credit cards, this is a very easy and absolutely free way to do it. The company has no minimum requirements for sales, no maintenance or sign up fees.