Square payment device for iPhone (with iPhone 4 fix)

Today I received my Square device from SquareUp.com which allows me to accept credit cards as payment for services that I do for my customers.  The device plugs into the iPhone and when used with the Square app for iPhone lets me specify a charge amount, type a not and then swipe the customers credit/debit card. Once swiped (correctly, more on that later) the a new screen appears in landscape and requests the customer to sign their name using their finger. Press one final button and it shows the transaction is complete.

Optionally you can send the customer a receipt via email which will contain a link that shows a map of where the transaction took place, when, my picture and the note that what specified when starting the transaction.

When testing this $1.00 test transaction I received $0.82 in my bank account.

Square states the following on their site regarding the service fees per transaction:

Card-present (swiped) rate: 2.75% + 15¢

Card-not-present (keyed-in) rate: 3.5% + 15¢

Problems (and the solution to the iPhone 4 issue)

One problem I had with swiping the card is that the device kinda “shorts out” when the Square is plugged in to an iPhone 4. Previous iPhones don’t have the antenna external to the unit which is how it “shorts out”. I applied a small amount of clean nail polish to the gold base of the headphone jack which creates a small barrier between the iphone and the gold base of the Square.

I added the red there to show where I put the small amount of clear nail polish.