We highly recommend using the WPS Pro Wireless Print Server. It's made by DNP and you can purchase it for a mere $219 at amazon.com, bhphoto.com, etc.
The WPS Pro eliminates the need for a laptop and software. We recommend the DS40, DS620 and DS80 printers for use with the WPS Pro. You can pool multiple printers using one WPS Pro as well.
To print from FotoZap to the WPS Pro, first connect the iPad's wifi to the WPS Pro. Then confirm in the FotoZap app's Settings screen that the printer is connected. Toggle Printing on, select your printer and send a test print from the app.
You can find more information on the WPS Pro at the DNP website here.