I want a phone that behaves like windows/linux desktop where I can freely download any application from any website and run it. And where the development can be as simple as hooking said phone to bigger screen, keyboard, mouse, launching some IDE and where I can code / design gui (delphi like) / compile (native please) / debug. Modern phone hardware has enough power for these tasks being done in place.

It should also have some low power built in core dedicated strictly to phone tasks that would have a priority over everything else.

Add to that decent hardware.