Two cameras that have been traveling in my shirt pocket lately are the Nikon Coolpix S800C and the Sony RX-100. Let's get the good news out of the way first.
The Sony RX-100 is definitely a recommended product. It's a little big for shirt pockets due to the slight protrusion of the lens, and it's fairly dense in weight for its size, but it's a pocketable camera nonetheless. With a 20mp 1" sensor at its core, it lives in the realm of "big sensor compact cameras." A 28-100mm f/1.8-4.9 equivalent lens sits in front of the sensor. The 28mm side is pretty good overall (and fast), the 100mm side a little weaker in the corners (and slow in aperture at f/4.9).
Sony did a good job of not getting carried away with the UI on this camera. It nicely straddles the better Sony compacts and the NEX/DSLR offerings in terms of controls and complexity. The mode dial doesn't tend to move, most of the rest is handled by the four buttons arrayed around the Direction pad wheel. Sony did what Nikon should have done on the Nikon 1: a function button gets you one step closer to other common core functions (exposure compensation, ISO, White Balance, Dynamic Range enhancement are what I've set it to; you get up to seven items out 17 possible ones, so I'd be surprised if you can't find a few you want the FN button to pull up). So, to change ISO means I press the FN button, navigate to ISO, use the dial to set it. Much more direct than menu diving (which you can also do). The menus themselves are very DSLR-like, extensive, but organized (why is the NEX so crazy in its menu system?). The camera also has a control ring that you can customize to 9 things. I tend to leave mine set to aperture (in aperture priority exposure mode).
I wish the tripod socket were lens centered and away from the battery compartment door (makes for awkward Arca plate use for tripod work), and I wish the battery was bigger (330 image CIPA, which I've yet to achieve), and it would have been nice to get a hot shoe up top (the camera has a small built-in flash). The camera could also use a better grip (hint: get Richard Franiec's). But we're talking about a shirt pocket camera here, so I'll put up with those things for a competent camera.
And the RX-100 is beyond competent. Heck, if you're a vidiot, uh, I mean videographer, the RX-100 has become one of the best of the small cameras: largish sensor and 1080P/60 (unfortunately 1080P/50 in PAL countries). But you want to know about stills.
Okay, still photography is quite good, too. As long as you aren't treating this as 20mp to print as big as possible I think you'll be quite happy with the results. At pixel level, the RX-100 can fail you a bit, in other words. But for modest output sizes, it's actually quite good. Indeed, Sony has a couple of interesting twists that make it not just good for bright light, but for low light, as well. The Hand Held Twilight mode takes multiple frames and stacks them, subtracting out noise (and ignoring frames with motion in them). Thus, in a pinch (and again not trying to print 24" wide or larger), you can use this camera up to ISO 6400 with a bit of care. At 28mm, f/1.8, and ISO 6400 there's not a lot you can't photograph. At 100mm f/4.9, okay, you're a little limited. But again, this is a shirt pocket camera we're talking about. For 8x10 or even 11x14" prints, this camera produces images better than many of the DSLRs we were using only a five or six years ago. That said, the Sony's JPEG engine is still a little NR heavy, and the raw results will need careful work to optimize. Remember, you've got slightly limited DR to work with due to the small photosite size (DxO says 12.4 stops, but it's more constrained than that in practical use).
Compared to other pocket cameras, it's no contest. Cameras like the Canon S100 or the Olympus XZ-1 can't match the output of the RX-100, in my opinion. Compared to the Canon G1x, it's a close call except for one thing: the G1x is massive compared to the RX-100. I like the handling and additional features (swivel LCD) of the G1x a lot, but it's a handful and requires a big jacket pocket minimum. Diffraction is also a bit less of an issue on a G1x than the RX100 if you're going to push each to their maximum print size.
Meanwhile, we have the Nikon S800C. Overpriced and underperformed would be two simple ways of describing it. The funny thing is that I thought that it might be an interesting tool for bloggers looking for more camera than their iOS or Android phone/tablet gave them, but, if anything, those folk would be better off with any number of other solutions that just use a simple connection, like WiFi.
When I talked about what was to become the S800C with Nikon executives several years back, one of the things they didn't get is that you want to simplify user workflow, not complicate it. I haven't yet found a way that the S800C simplifies workflow, but I've found plenty of ways that it complicates it. As compared, say, to an Eye-Fi card.
In terms of camera functions, the S800C is dirt basic. Easy auto, Auto, or Scene modes, basically. A few modifiers, such as exposure compensation. But everything is pretty much auto. As in auto bought a different camera.
Up front we have a 25-250mm f/3.2-5.8 lens, which I think is the main selling point versus just using your smartphone's camera.
But let's jump to the negatives: battery life is abysmal, especially if you try to use the Android side of the thing for anything. The camera always uses slow shutter speeds over higher ISO to keep the small sensor from showing a lot of noise, but that means motion blur is something that happens a lot. The color rendering is the worst I've seen out of a Nikon camera (maybe I haven't looked at enough recent Coolpix). The flash overproduces for short distances, doesn't have enough reach for medium to long ones. Startup (and shutdown) time is a bit slow. The device is either a camera (lens out) or a version 2.3 Android phone without the phone (lens in), which makes going back and forth slower because the lens has to be moved in and out. As an Android device, it's basic and relatively poor. I'd rather browse, do email, look at maps, or any of the other things I'd normally do on an Android device on a dedicated Android device with a bigger and better display, and a better touch-screen.
In terms of camera, the S800C is basically a S6300. So you're paying US$150 for the Android additions (and a slightly bigger screen). But wait, you can set a few things on an S6300 you can't on the S800C (ISO ranges, for example). Plus you get 230 images per charge rather than 140 with the same battery. That Android graft-on is a bit of a power consumption hog.
And yes, it's an Android graft-on. The S800C is a frankencamera, built of parts from two different bodies and forced to work together. It's not a great camera. Certainly no better than any other US$199 camera on the market, of which there are many that seem better to me, so why pay the extra money? Get an Eye-Fi card for a non-Android compact instead. The S800C is not a great Android device (and will remain version 2.3 forever, probably).
The real shame here is that Nikon didn't add anything to the Android side to show us what this camera might really do. The Nikon Picturetown application isn't even pre-loaded on my copy! So I'm left to the devices of Google Play's application store. Let's see, let me try a couple of things in the Photography category. Oops. These apps can't control the S800C's camera. Well, gee, what can I get that would work?
Well, I found a couple of apps that can do post processing on an image I take with the S800C. But I can already use those on my phone/tablet if I can just get my image over there. Which I can with a lot of cameras that have WiFi, or an EyeFi card in many cameras. I'm not going to waste what little battery I've got in the S800C on those apps.
In the next story I wrote about ecosystems. Nikon has joined an ecosystem (Android) and diminished it (the sum of the parts is less than the sum of the parts, as none of the camera apps I've tried work with the camera ;~). That's exactly the wrong route to success, both for an individual product and for the ecosystem.
The S800C gets an Epic Fail rating from me. Not just a Not Recommended, but a total failure on the part of Nikon to put out a product that deserves to exist.
If you don't believe me, try Samsung's Android camera next to Nikon's. Even though I wouldn't recommend it, either, Samsung did a far better job of creating something useful. Unfortunately, it's even more expensive.
Still, the right answer is simple: enable communication on the camera and do the heavy lifting with something that's designed for heavy lifting (smartphone, tablet, laptop, desktop, whatever). Wannabe phone cameras without the phone need not apply.