This is Agalychnis callidryas, the Red-eyed Tree Frog. It is native to rainforests in Central America. "Red-eyed tree frogs are not poisonous and rely on camouflage to protect themselves. During the day, they remain motionless, cover their blue sides with their back legs, tuck their bright feet under their stomach, and shut their red eyes. Thus, they appear almost completely green, and well hidden among the foliage." Wikipedia.
His eyes are freaking huge! He must see something he really wants. Maybe he is eying a nice juicy fly. If I was walking in a rainforest and I saw those eyes staring at me, I would be a little creeped out.