The fact that you can place all your products anywhere on the mat and it charges at high speed, as you can see in that video placement is important with that chinese knockoff because underneath it's just a couple of single (small) coils (which also means that power on that thing is maximum 5w per device and probably a lot less).
Airpower will use an array of bigger and smaller coils which means that it will charge anywhere on the mat wherever you put it and all that with 7.5-10w charging per device. If it was just a couple of single coils in an enclosure it would have been out in 2017 without any issues. And such an array still doesn't exist on any of the other wireless chargers.
So is spent an hour on reading about the Qi technology.
From what I recalled from electrical engineering, modeling magnetic and electric fields from coils is not simple, especially if you have several of them at different frequencies overlapping or at least in close proximity.
From my reading I kind of deduct the that while overlapping multicoil systems are supported by the newest Qi standard, it effectively will always just power one coil at the time. This enables more free placement.
Now in theory you can put a lot of these in the device, and just have an advanced controller switching on the ones needed. They are also rather cheap and thin so the difference between having 10 or 20
is not that big from a cost or design perspective.
But if you have some of them too close to each other powered on the interference will cause issues in the form of reduced efficiency. This comes not only from the overlapping magnetic fields but the dynamic nature of them. The standard is intelligent enough to find the most efficient frequency, with many devices this can cause fluctuating magnetic fields that potentially have very high peaks. (Think about sinewaves with different periodicity) The standard itself supports much higher outputs than what is needed for phones, but likely with a significant heat generation. Thus there will be a tradeoff between charging rate with multidevices and heat.
Finally there is the problem of apple watch. Because apple was being apple they tinkered with the wireless charging so it is not compatible with all Qi charger, but at least the technology is kind of the same, even if it's an older standard.
Now I don't know how problematic these constraints are, nor am I an expert in these fields, so someone much smarter have to do the math.
My guess is that Apple has a prototype/product that can charge devices at the same time, but the usability is not Apple-like. Maybe if devices are too close they charge too slow, or heat too much or don't charge at all. It could also have something to do with the Apple Watch.
And fully speculating, this is a product dreamed up by the Ive-league and the constraints were set with respect to the usual thinness and quality that Apple products offer, or from an engineering standpoint impossible with current technology.
I am however more positive about this product after learning about the challenges but find it too expensive for my purposes (I know there is no price yet, but I am pretty confident about 150+). I am also sure apple won't give up on this and we will see it at some point. At latest when the first iPhone without the port is released.
If there is a demand I could add links on where I puzzled this together from.
