Apple stores print receipts from their iPod touch credit card readers. They probably use a custom solution with a server backend.
Square has a few wireless receipt printers it can work with.
I haven't yet seen a receipt printer that is airprint compatible though, allowing more apps to use it. While credit card acceptance and sales apps would obviously benefit, I can imagine a number of other uses for a small printer that prints bits of disposable information. The daily forecast, sudoku puzzles, today's schedule, todo lists, etc, for those who have to share their iPad with a spouse or children, for instance.
Are there air print receipt printers, or is there an easy way to set up a receipt printer, perhaps with an airprint server (device or software on the mac) that would allow this?
Best Answer
Most receipt printers I have seen use a wired ethernet connection, so you could add a slick Lantronix xPrintServer which uses AirPrint to avoid needing a computer running for your iOS devices to print to these specialized printers.
There are several reviews of this product, and the unit is physically about the size of three iPhone 4 stacked in a neat pile. It is intended to support between 7 and 10 printers before you need to buy a second device. I am not clear whether you can set this up from iOS, but it works well once you have it set up.
The day will come when label printers ship with wireless chips and AirPrint embedded, but that day is not yet here.