Reality check
Wifi isn't an issue. The lens and the phone communicate via bluetooth.
No, the lens does not have a display of it's own. That would be pointless. It is meant to attach to the back of the phone - the phone acting as display and as controller. As it stands now, even good quality camera bodies are little more than a sensor, a computer, display, and controls. It makes some sense to let a smartphone be the computer, display, and controls if the sensor can be embedded on the back of the lens.
people have a point about this product potentially having trouble finding an audience. As you say, enthusiasts won't accept it and non-enthusiasts will live with the phone's built-in camera.
On the other hand, lots of people are buying Sony's RX100 for $700 and loving it. This has the same sensor and very similar lens - and as all photographers in the digital age know, it's all about the sensor and the lens. So if I were someone interested in an RX100, it makes perfect sense to use this instead, with the phone already in your pocket. The lens can just stay in your jacket pocket or whatever when you are not using it.
By the way, phone cameras may seem amazing, but the 1" sensor here is approximately 20 TIMES the surface area. The image quality (to anyone savvy enough to notice) would be a huge improvement, especially when viewing them via some other format than Facebook...
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I've certainly been wrong before but this seems like the most retarded idea of all-time to me. Spend 500 bucks on a lens/sensor assembly that's only one phone generation away from sitting in your junk drawer when you could probably buy a 100 buck point and shoot that will take better pics without pounding away on the iPhone screen for day and half to change a friggin' shooting setting.
Sure. Sign me up!
I don't know any details, but it seems obvious to me that the lens attaches via a phone case that is low-tech and simple to manufacture in any number of sizes and styles. You change phones, and IF you need a different size case for that new phone, you simply buy another from Sony in the size/brand you need. Probably no more than $29. The lens is still fully functional after you change phones, assuming your new phone supports the app and sony makes the case that fits.