Makr App for iPad lets you print cards and invitations
Makr App for iPad:
Makr is an iPad app that lets you create invitations, greeting cards, business cards, stickers and other graphic printing yourself. All by yourself, without having to need a designer. You choose from a number of templates in categories such as business, parties, weddings, babies, holidays or home. Afterwards adjust it to your own needs and download a high-resolution PDF to print on your printer at home.
Download: Makr (free, iPad, iOS 6.0 +)