Hmm. This seems to indicate you need internet connection:
Print from virtually anywhere - print wirelessly from your smartphone, tablet and Internet-connected PC.[1]
[1] Requires an Internet connection to an HP web-enabled printer and HP ePrint account registration. For a list of eligible printers, supported documents and image types, and other HP ePrint details, see hpconnected.com. Mobile devices and PCs require Internet connection and email capability. May require wireless access point. ...