I never really used it for much, a bit of light browsing and really just as a gimmick, buit yeah, there was a desktop of sorts and you could use all the apps, and the touchpad/mouse thing worked. You could attach a bluetooth keyboard too, IIRC.
Kindof a shame my iphone doesn't do this (I assume, I haven't tried), but I'm not sure if I'd use it.
I might give it a go when I upgrade to a USB-C model.
Works fine. I don't know if you can format drives, but you can definitely read and write to external disks and network shares.
Yeah it's painful to use! You can set up a mouse, and use a physical keyboard for input, but it doesn't attempt to do any more than mirror the screen onto the external device by default.
Huawei's desktop mode was limited, but I think you're right - you can say the iphone has good device compatibility, but there's not a good way to use it docked. Not that the android ones were 'good', but they made an attempt!