Apple’s (NASDAQ:AAPL) next-generation iPad, presumably dubbed the iPad 6, could be the next-generation version of the existing iPad Air with some key improvements while the rumored bigger iPad and the third-generation iPad mini may not hit the market until 2015, an analyst said in a research note.

According to Ming-Chi Kuo of KGI Securities, overall iPad shipments are expected to decline this year as the iPad Air could be the only iPad model to see a refresh in 2014 with new features and specs, such as a next-generation A8 processor and the Touch ID fingerprint sensor. While the new iPad Air is likely to be released in the third quarter of this year, the rumored 12.9-inch iPad and the successor to the Retina iPad mini may be launched only in 2015.

Here is an excerpt from Kuo’s note, obtained by MacRumors:

Compared with lower-margin iPad mini with Retina display, which shipments has been tepid, higher-margin iPad Air was a hot selling item in 4Q13, which will slow Apple in developing new iPad mini models. We believe Apple plans to launch upgraded iPad Air early this year, and will accelerate development of 12.9” iPad. As such, more resources will be allocated to these two products, which will affect the progress of the development of new iPad mini. All told, we think chances of the debut of a new iPad mini in 2H14 are slim. In addition, the 12.9” iPad is unlikely to be offered in 2014. For these reasons, we predict the only new iPad product in 2H14 will be the upgraded iPad Air.

While this is the first time that an analyst has said that Apple may not update the iPad mini this year, Rhoda Alexander, an analyst at IHS, also said last month that the larger 12.9-inch iPad is not likely to be released anytime soon.

Kuo said that the 12.9-inch iPad could be a growth driver for Apple, and it would require a revised operating system if the company is to take advantage of the bigger display. According to him, total iPad shipments will fall to fewer than 30 million units in the first half of 2014, down from 34 million units in the first half of 2013, Apple Insider reported.

In addition to iPads, Kuo also said that Apple has prioritized finishing the operating system for the "iWatch," which is expected to be launched this year.