I would be interested in knowing more about that myself. I am looking to start using cards for payment, but the fees are really high.
The Square is 2.75 % no monthly. Intuit has the same month to month rate with an option of a lower interest rate with a monthly charge. We use QB software which may make the Intuit more attractive if it interacts with our POS software. Another advantage to the phone swiper is that it does deposit next day vs. the typical deposit schedule of 3 days for the terminal swiper. It also take the fee per transaction vs a monthly debit, so you see the real time amount of money in your account. We are not supposed to add on extra for charge cards taken on the terminal, but I cannot find anything saying we cannot with this service style. So theoretically you 'could' pass that along to the consumer?
I asked some of my techie colleagues. This is what they told me: You lose 2.75% on each transaction which is slightly more than normal, but it's a lot more convenient. They currently process 5 Billion dollars a year. Tons of small businesses use them and it's got very good reviews, you can read more about it at squareup.com
You can sign up for one and they will mail it to your house. http://store.apple.com/us/product/H8332LL/A If you have any specific questions, let me know, i'll ask :)
we have been very satisfied with our use of it thus far; we have only used it a few times though