Yes. _Bootstrap yourself to write an OS from scratch_. As it says at the very top: "How to write an operating system from scratch by reading hardware datashee

Yes. _Bootstrap yourself to write an OS from scratch_. As it says at the very top: "How to write an operating system from scratch by reading hardware datasheets. In the real world, it works like that. You won't be able to consult Google for a quick answer." To write an Android clone, you'll need to understand how cellphones work, which involves reading hardware datasheets (and possibly signing a few dozen or so NDAs to obtain the information).