I would say that if measured by the knowledge and science involved the N800 is probably orders of magnitude more complex than a simple car like lets say from 20 years ago. I mean an Engine and all the other stuff in a car is plain Newtonian physics albeit on a high level. All it's parts could be produced with 60-70 year old machinery and a wokrking bare bone car could probably be produced with the tools and physics knowledge the old greeks had if enough effort had been put into it. On the other side the knowledge needed to built something like the N800 is orders of magnitutes higher. It involves knowledge of complicated electromagnetic phenomena (just imagine how much you have to know about the nature of electromagnatic waves to build a working WiFi). It needs modern chemical science for it's display and extremely high tech laser technology as well as chemical science for it's CPU. Then it will need you to know a lot about mathematics including knowledge that is not even 60 years old. And it will need you some hundred thousand wokring hours for the programming. Maybe some hundred man hours if you have to rebuild everything from an assembler to a c compiler and so forth. For the N810 you would have to know even more, for example building a GPS is impossible without knowledge of special and general relativity.