Based on various reports, and a lack of leaks, it does not look promising that Apple will release a third-generation iPad Air this year. It may be hard to believe that the company will forego its flagship 9-inch iPad in favor of a larger 12-inch model, but that's where all signs are pointing. The rumor mill and some analysts believe that Apple will only release a revamped iPad mini 4 and 12-inch iPad Pro in 2015 due to slumping tablet sales.
It is no secret that worldwide tablet sales are on a slide and that the iPad is not immune. Apple recently announced a 17.9% year-over-year decline in iPad sales and CEO Tim Cook has had to defend the tablet twice after seperate earning calls. This doesn't mean the iPad is selling poorly, Apple still sold 10.9 million units in Q2 of 2015, but it does show that interest in tablets overall has slown down.