To print from an apple mobile device you must use Apple Airprint
How to use AirPrint
AirPrint is the built in support for printing from mobile devices supplied by Apple.
It uses Wi-Fi to submit jobs to an AirPrint compatible printer on the local wireless network. It is only compatible with certain printers.
You can find a complete list of Airprint compatible printers on the Apple website.
The downside of airprint is that you will need a wireless network to connect your phone / ipad and the printer.
Apple have some great instructions on how to use Airprint here
As mobile printing can be quite tricky, we recommend printing an invoice or job report to a PDF and then emailing the PDF to the customer where possible.
This method is faster and paperless.