"What Apple did do was market this newer form factor very successfully"
No, what Apple did was to bring its 20 years of experience making OSs to a mobile phone. Most of the iOS libraries are the same that in macOS.
Those are incredible low level-very efficient and smart work tested by millions of people on the real world for years, and very good designed.(Apple have really great designers not only on the outside)
The quality of this thing was(and is, Windows internals are sh*t, I had disassembled both, it always was about shipping fast and rough, fix later attitude) much bigger than anything else in the market at this time.
Google did the same porting Linux to mobile.