> "WiFi direct" is yet another completely different thing, that is meant for peer-to-peer connections (note: two communication partners) without needing an AP, which 802.11 consumer standards (b,g,n,ac) all did and do otherwise.
Wi-Fi Direct is nothing more than running (e.g., 802.11n) software AP with WPS on one device ("Group Owner") and having (multiple) peers connect to it to form a "group" -- it's just a normal AP, you can even connect legacy Wi-Fi devices to it. It does add functionality to automatically negotiate which device becomes the access point and to do some service discovery on the link layer before connecting.
The way you just described WiFi Direct sounds closer to true mobile-to-mobile mesh connectivity than what is described above. WiFi Direct allows nodes to trade off AP duties; EasyMesh allows nodes to optimize AP selection; scatternet allowed (if I recall correctly) multi-AP piconet connections over Bluetooth, using application layer as a workaround for inadequate link-layer protocols. ... But I wouldn't say it's like comparing apples & oranges; more like comparing Newtons & Macintosh. It seems obvious to me that they approach the same challenge (flexible connectivity) from different directions, but if you have time, please clarify how these three protocols are substantially different in purpose?
The problem with WiFi Direct is that all its local mobile-to-mobile capabilities are disabled if the group doesn't have a node connected to a tower at all times. For example, you can't have three devices up in the mountains exchange files or messages, unless one of them can get the OK from a service provider's tower. WiFi Direct stops as soon as you lose cellular signal or experience a service timeout. It's crippled by design.
EasyMesh doesn't seem to offer any neighbor-to-neighbor utility; It appears to be focused solely on expanding coverage of single-point-of-control networks which are already overcrowded (hence the need for so many range extenders). When are we not in range of half a dozen or more WiFi networks?
I see adding more APs as an exercise in futility. The primary issue is overcrowding, not signal strength. Remove all the other nearby networks & one router easily reaches across most buildings.
Sorry, I guess that's two topics in one comment, but I'll repeat my primary question: In what way are these different approaches "completely" different? They seem to all be chasing roughly the same goal. I also feel that "mesh" has stagnated due to lack of hardware support (& accompanying lack of open source firmware).
Wifi direct exists independent of cell phones. There's even a windows 10 protocol adapter for it. The phone implementation could be terribly broken, but the standard says nothing about 4G connectivity or go-ahead (as it shouldn't!).
Wi-Fi Direct is nothing more than running (e.g., 802.11n) software AP with WPS on one device ("Group Owner") and having (multiple) peers connect to it to form a "group" -- it's just a normal AP, you can even connect legacy Wi-Fi devices to it. It does add functionality to automatically negotiate which device becomes the access point and to do some service discovery on the link layer before connecting.