Initially expected the iPad Air 3 to launch in 2015 but instead Apple gave us the iPad Pro and iPad Mini 4. And to be honest, that kept us satisfied. The iPad Pro feels like an innovative, new product while the iPad Mini 4 is a big improvement upon the iPad Mini 3.
Rumor is that Apple wanted to hold off releasing the third iteration of the iPad Air as it didn’t want to overload consumers with too many different choices. Good decision.