Had exactly the same problem last night with our Epson 7515. My Missus was trying to print from her iPhone. Queue is stacking up micely but nothing coming out....
W: "Why can't we turn it off/on?"
Me: "Not now love, who's the IT expert?"
W: "Yes but..."
Me: "I'll have it in a minute love."
W: "We could just reset the printer, look there's an option on the menu."
Me: "Yes but darling, it's working fine from the PCs, it's got to be your phone."
W: "What harm can it do to reset the printer config?"
Me: "OK but I can't see what good a reset will do..."
Wife: "Oooh it's working now look, it's printed my stuff!"
( *grumble* bloody women, bloody well always right....bloody well get back to kitchen... *grumble* )