"Forget the bulletin board analogy, Uncle, that's just the Network! The phone is more than that!"

Zuko wracks his brain, and comes up with an even worse analogy.

"Think of this like... Like the world's smallest, smartest, fastest messenger hawk! A hawk so stealthy you can't even see it! Combined with... um... an iguana parrot that can mimic your voice perfectly, and, uh— ...that can paint magic moving portraits..."

Okay, the analogy got away from him. But he reaches his phone out and takes a short video of himself pulling an uncomfortable face at the camera, and sends it to Iroh to play back on his phone.