Both tablets represent the pinnacle of their respective manufacturers' mobile technology, and with both launching so closely together, the fight for your wallet has never been more fierce.
For once, the Nexus 9 isn't a tablet that's kind on the wallet, coming in at a price that's not far off Apple's. That said, it's packing some similar technology and promises a very powerful screen experience coupled with a next-gen processor under the hood.
The iPad Air 2 is already off to a great start (as our glowing 5 star review will attest), but does that mean the Nexus 9 is out of the running before it's even been released? Let's find out...
The Apple iPad Air 2 is just 6.1mm thick – 18% thinner than the already impressively thin iPad Air.
This makes it one of the thinnest tablets on the market today. One of the ways Apple has managed to make the iPad Air 2 so thin is by removing the air gaps between the different layers when building the screen.
HTC, the manufacturer with whom Google is working to build the Nexus 9, has also got a few tricks up its sleeve to keep its new tablet as slim as possible. Known as 'zero gap aluminium construction', the idea is to make the Nexus 9 look like it's been carved out of a single sheet of metal.
Not only does this give the Nexus 9 a premium feel, but it also helps keep the thickness down to just 7.9mm - pretty thin, but not quite as svelte as the iPad Air 2.
For the first time in one of its tablets, Apple has included its Touch ID sensor with the iPad Air 2, which also doubles as the home button. This lets you unlock the tablet with just your fingerprint, a security feature that the Nexus 9 doesn't have.
While some people may have been disappointed with Apple's decision to keep the resolution of the iPad Air 2 the same as the original iPad Air, that doesn't mean the screen is a slouch in the looks department.
The 9.7-inch Retina display has a 2,048 x 1,536 resolution with a pixel density of 264ppi (pixels per inch).
In contrast, the Nexus 9 features a smaller 8.9-inch IPS LCD screen with an iPad Air 2-matching 2,048 x 1,536. Because it fits the same resolution into a smaller screen, the Nexus 9 has a higher pixel density of 287ppi.
Both the Nexus 9 and the iPad Air 2's screens have 4:3 aspect ratios, which are shorter than other competing tablets.
The higher the pixel density the crisper the image, so on paper it looks like the Nexus 9 has the advantage. That doesn't mean it's a complete wash, though, with Apple's design choices paying dividends when it comes to image quality.
The iPad Air 2's resolution is the same as the iPad Air (and the Nexus 9), but Apple has included a number of new technologies. Removing the air between the layers of the screen doesn't just make the iPad Air 2 incredibly thin, it also helps the screen benefit from deeper blacks and more vibrant colours, especially compared to the Nexus 9.
The new process also means the screen is less reflective, which helps viewing the screen in certain light conditions.
The iPad Air 2 saw a number of improvements to both its front-facing and rear-facing cameras. The front-facing Facetime HD camera has had its resolution bumped up to 1.5MP, while the rear iSight camera is now 8MP with an f/2.4 aperture.
It can record 1080p video with digital stabilisation and comes with a number of features such as burst mode, timelapse and slo-mo mode.
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Matt is TechRadar's Managing Editor for Core Tech, looking after computing and mobile technology. Having written for a number of publications such as PC Plus, PC Format, T3 and Linux Format, there's no aspect of technology that Matt isn't passionate about, especially computing and PC gaming. Ever since he got an Amiga A500+ for Christmas in 1991, he's loved using (and playing on) computers, and will talk endlessly about how The Secret of Monkey Island is the best game ever made.