Even a 40-50€ lens would be a huge upgrade to any smartphone.

If I read the paper correctly the lens will have its own sensor. Integrated in it. It will also use laser to communicate with the phone. I doubt it will ever be that 'cheap'.

Also, for this lens to be something enough customers will want to purchase, it won't be allowed to be a basic lens. Marketing has taken over what little remained of photography in the photography business and many people don't buy a camera anymore, they buy specs (no blaming, here).

So this lens will need to open wide. Forget a basic f5.6, looking at actual smartphone specs I wouldn't be surprised to see it being f2.8 or wider (no matter how crazy that would be to anyone knowing a little about photography because that's only marketing talking) and that can't be cheap. And then, it will need to seduce a large audience of non expert photographers by offering them a large enough range. So we probably can forget a fixed 35 or 50mm (even if those would be amazing tools). We may even forget a basic zoom with say a reasonable but limited 35-80mm range (here again, limited only in the marketing world that is now ruling). At least, to begin with and in order to create a viable new market, one will need to offer some high-quality lenses, aka expensive. If there is a cheap lens available it won't be sold extra, almost no one will rush to buy it, and it will need to be sold with the phone, included in its price or at a serious discount. Like one can buy a cheap 'kit lens' with most bodies. But kit lenses don't have sensors and they don't work using laser. And we've not yet considered the extra weight, bulk, and inconvenience of carrying a lens that the user will need to fix every time they want to use it. Instead of just snapping a picture with their phone's integrated camera. And, like I mentioned earlier, the extra fragility a magnetic systems implies to me.

So, really I don't see how it will be doable. To be clear, I'm not saying any of that will happen or that it will fail. I can't predict the future (I would be rich :p). I just shared my first reaction looking at the pictures and reading how the lens was supposed to behave. Never intended it to be a deep consideration of the question.

If I was to seriously consider it? More than an new type of lens (extra cost and bulk and fragility and less pocketability), if I was an investor, I would put a lot more of my money on the AI side of photography.

AI post- and live-treatments should revolutionize the way we take pictures and even the way we think about photography. Exactly photography itself, back then, revolutionized the way painters had to think about their art and how they practiced it (and how they were selling it to their customers).

What matters here is that all those AI changes that we yet to see appearing won't require much, if any, change in lens design and photographic gear itself, nor on the phone thickness. It's all software. Meaning no extra bulk, and no extra-cost... beside the unavoidable subscription that will undoubtedly be associated with using it (here too no need to be predicting the future to see that coming ;)

Like I said, I'm impressed by the concept and would love to see it work for real. But I would not put a cent of my (very hypothetical) investor money on it.

Define "decent". My smartphone camera is "decent" to me, but for others, they swear their iPhone 20X SE abc whatever has the only smartphone camera they can trust. Others can only chuckle at that and say "single lens reflex or nothing", then it goes on to full frame vs APS-C, and so on 🤷