Android tablets are going through an interesting transition right now. We're seeing the first few hints of 64-bit support, 4:3 screens, and some powerful gaming features. However, these products are still imperfect. I don't think there's such a thing as the perfect Android tablet for everyone right now, but there are a few good ones that might work well for you.
Let's check out all the top tablets on the market and see what they all have going for them.
If you like having access to the latest software and dig the 4:3 form factor, the Nexus 9 might be an appealing option. This tablet runs on a Denver dual-core Nvidia Tegra K1 chip with 2GB of RAM and 16-32GB of storage. The centerpiece is clearly the screen, which is above average compared to most Android tablets. It's an 8.9-inch LCD with a resolution of 2048x1536, just like the iPad. At 8.9-inches, a widescreen tablet would be awkward to use in portrait orientation, but the the N9 is quite comfy.
The Nexus 9 runs Android 5.0/5.1 Lollipop without any OEM junk added. This is Android as Google intended with updates more or less guaranteed for at least two years. The Nexus 9 might fall back to second priority in a year or so when new devices come out, but you won't be left to rot on an old version of Android within the expected life of this tablet. There are also full system images for the Nexus 9 and an unlockable bootloader, making for easy modding (and fixing your mistakes so you don't end up with a brick).
I think the biggest knock against the Nexus 9 is that the build quality simply isn't where it needs to be for a $400 and up tablet. The buttons are a little mushy, the soft touch plastic feels a little cheap, and it's slightly heavy. More recent production runs of the Nexus 9 are much more solid. It still takes a weirdly long time to charge, though.
More problematic is the state of the Nexus 9's software. It's overall a better experience than many Android tablets, but the N9 still stutters and hangs more than it should. Nvidia's Denver CPU core has a lot of power, but it seems like it's not being fully harnessed in the N9. Hopefully a future software update gives this tablet the extra boost it needs to be a better experience.
The Nexus 9 is a good tablet, but it's pricey. If you can find one on sale, it might be a good buy. Even if you can't the form factor makes it worth considering.