If you want an Android slate with a camera that's not a total afterthought, your only real option is Samsung's Tab S line.
The Android tablet space is kinda weird right now, ahead of major changes expected later in the year in the world of Google laptops, tablets, and convertibles. If you need an Android tablet right this second, the best options are Google's Pixel C and Samsung's Galaxy Tab S2 series, soon to be superseded by the Tab S3. For more laptop-like productivity, there's Lenovo's Yoga Book. But of this subset of decent Android tablets, only Samsung's Tab S2 treats the camera as more than an afterthought.
Before we begin, it's worth noting that the Galaxy Tab S3 will be landing imminently, with an upgraded 13-megapixel shooter behind an f/1.9 lens — alongside improved post-processing, thanks to the Snapdragon 820 processor. So if you can hold out a little longer, the Tab S3 will offer higher-resolution snaps.
Few Android tablets prioritize photography, but the Tab S2 makes a decent effort.
There's also the question of whether a tablet is the best device to be taking photos on to begin with. Larger Android phones, like the 5.9-inch Huawei Mate 9 and LG V20, have smaller displays than many of the tablets out there, but depending on your use case, may be a better fit and will certainly take better photos than a full-sized slate. Tablet photography still carries something of a stigma, after all.
Anyway, back to the Tab S2. This model, released in 8.0- and 9.7-inch flavors in late 2015, features an 8-megapixel rear camera behind an f/1.9 lens and video recording up to 1440p. And right now, it remains the best-performing camera in an Android tablet.
In our review of the 8-inch version, Andrew Martonik talked up its photographic quality relative to competitors, and we've seen little in the past year to challenge the Tab S2's solid (if unspectacular performance.)
Images are pretty good, at least for a tablet but won't be rivaling shots from last year's flagship or even some mid-range phones. Dynamic range isn't too great, and while the camera is quick to capture shots, I wasn't blown away by the results. It was useful for snapping pictures of things around the house and getting the occasional shot when I was out and about, but it's worth remembering that the phone you certainly have on you anyway will probably offer a better experience.
The "for a tablet" part is important there. Android tablets have struggled to shrug off the perception that they are, first and foremost, content consumption devices, and so the competition here is relatively weak.The bottom line: Even in this, the most capable of Android tablet cameras, you can expect relatively run-of-the-mill low-light performance. And don't expect to be blown away by daylight performance either, especially if you're judging it by the standards of modern smartphones.
Nevertheless, if you've gotta be that guy taking pictures on his tablet and you don't want an iPad, this is the best performer in a tricky market segment.