The original note, as written at the time
SIDE FLASH CAMERA. A smartphone camera that is angled through the side of the narrow device so one can take pictures of the context and look like they are texting. This camera could also be mounted onto an internal motor so that it can adapt to any position the user desires.
Ongoing development
A phone camera angled through the side of the narrow device, so that a person can photograph the scene in front of them while appearing to be texting. Mounted on an internal motor so it can take any position the user wants.
The first thing to be honest about is what this is for. Partly it is documentary: the thing happening in front of you that you want recorded without becoming the person recording it. Partly it is the other thing, and the other thing is why a manufacturer will hesitate.
But the second half of the note is the better idea and it has nothing to do with concealment. A camera on a motorised mount inside a thin body can point anywhere, which means the device stops having a front and a back. Today every phone has a camera pointing at the world and a camera pointing at you, and the difference between them is a whole design assumption about who is the subject.
A camera that can aim anywhere dissolves that, and the useful version is not stealthy at all — it is a phone you can set on a table and point at a whiteboard, or at a ceiling, or at a document, without propping it against a cup.
There is a real principle here about the relationship between a device’s shape and its function. We made phones flat and then arranged the cameras around the flatness, and every awkward accessory since is a consequence.
The risk worth naming: a camera that can be aimed while the device appears idle is a surveillance instrument, and it will be restricted or it will be misused. Any honest version needs a physical shutter and an unmistakable indicator, because a thing that can look without being seen looking is a different class of object.