I was, as they say, nerdsniped, by a video from element14's teardown series on the Sony DSC-QX10. Luckily, the slightly more exciting DSC-QX100 showed up on Ebay a few weeks later and I bought it for myself as a gag christmas present.
I understand that Sony wanted to answer the question of 'how can we make a phone take better photos?'. Other attempts included Samsung's Galaxy Zooms, and Panasonic's DMC-CM1, but Sony decided to build a Gadget. The Gadget is the imaging assembly out of 2012's best point-and-shoot, which pairs to your phone over WiFi. The issue is that the imaging sensor needs support components, which means that the Gadget ends up also containing the rest of the camera. Naively, one can keep trying to consider the Gadget as a phone accessory, but it is painfully apparent that this is actually a camera (namely a DSC-RX100M2) that has had almost its entire user interface lopped off and replaced with a half-functional smartphone app. Now we have to consider the Gadget against other cameras, and we ask a different question: 'Why would you want to intentionally introduce connection issues between the parts of your camera?'
What saves this gadget is the shutter button. Pairing is problematic - either Imaging Edge is buggy or Android's WiFi stack just doesn't want to pair to WiFi networks this quickly, likely both. You cannot expect to pair the two devices fast enough to set up any time-sensitive shot, and then the connection may still randomly fail. Sony recommends disabling bluetooth while using the camera, which does actually improve the image quality. This says some unfortunate things about the camera's WiFi hardware. It's also something you have to do manually, as is enabling WiFi. Android also pops up a security dialog to confirm you actually want to pair with your camera, and there is no way to automate this. Hence the pairing process is very involved for completely arbitrary reasons, and it will ruin some moments.
Which is why it's so important that you can just point and shoot.
There is something really unique about taking photos without any idea of how they will come out. You can, of course, do this with any camera, but here it's necessary. I found that my attitude to taking photos quickly changed, as I was forced to intuitively learn what the camera can and cannot do. It's definitely not reliable - most shots come out well, some come out very well. A significant proportion are garbage. To some extent this is user error, as when put on a tripod the camera does tend to take good photos. However, you're never entirely sure exactly what's going to be in focus, which can result in photos being 'artistic' in unexpected ways. Another funny issue is that a lot of photos come out wonky. The camera is almost completely cylindrical (to the point that it will roll away on some surfaces), which resulted in me nicknaming it the 'Barrelcam'. The lack of features on the outside of the Barrelcam messes with your natural ability to hold things upright, and I found a lot of photos come out rotated. It makes the photographer look a bit stupid. But it is worth listing the other features that Sony blessed the outside of the cylinder with. These are:
It's 63mm in every direction. It's probably not compact in the conventional sense, and definitely not if you put it in Sony's official case. I made it a 3D printed and leather padded case almost as soon as I got it, and I've recently replaced that with a new, much more polished version. I also had a Joby Gorillapod mount on it for a while, and now I've 3D printed a copy of that mount which is shifted a bit forward to allow clearance for the battery hatch. The wrist strap is also an important part of the puzzle, as there isn't really a confidence-inspiring way to hold the thing.
I've read about people sneaking it into concerts. I've personally stuck it through random urban holes to take photos while looking at the remote viewfinder on my phone. You can get some interesting shots that way, and have a lot of fun.
If you do shoot with it blind, as I primarily do, it's important to leave the camera in a reasonable shooting mode. I lost an entire days' worth of photos after accidentally leaving it on manual focus. On that note, it supports aperture priority, shutter priority, program auto, intelligent auto and super intelligent auto, with a true manual mode noticeably lacking. Intelligent auto is a scene-aware version of program auto. Super intelligent auto builds on that by adding automatic HDR shots. Unfortunately, those HDR shots will generally fail without a tripod, so it's worth sticking to intelligent auto for general use.
It's tempting to say that it takes 'surprisingly good photos', but the photos are roughly what one would expect from the imaging assembly. The sensor is a useful 1 inch diagonal with 20 megapixels. The lens is utilitarian, with a zoom range of 10.4-37.1 mm (28-100mm 35mm equivalent) and small amounts of chromatic abberation throughout. The lens just works adequately, with no particularly characterful defects. This results in the camera taking competent photos, which is entirely predictable. But it's also really strange, when you consider the fact that the photo came off a cylindrical camera which lacks most of its user interface and masquerades as a smartphone accessory.
Should you buy one? No. But somehow the purchase of this thing has resulted in me always carrying a camera, and I'm not sure I would carry anything else. I do really love it. I'm in the process of writing a QML app for controlling these cameras, and it's about half-done, but is already hitting the limits of Sony's bizarrely gimped API. I actually attempted a firmware modification on my first one... which is why there's now a second one. This is why I'm also now reverse engineering the bootloader in search of a way to fix the corrupt partition that causes the first one to bootloop. And, on the hardware side, I plan to glue one of those bayonet mounts to the back of my phone. I'll write more about the software side once I make progress on any of those fronts. In any case, I hope this was entertaining, if not very useful.