Here's a random thought:
Let's assume you're stranded on an Earth-like planet somewhere in a galaxy far away. You've made yourself a good shelter and ensured your survival for years to come with an adequate food and water supply.
Given all that, what steps would it take for you to build a computer at or close to the quality of a modern day smart phone? Where would you even begin?
Well if you're assuming zero technology and the same materials available, and nobody else you can't. It took humanity the culmination of thousands of years of math and science to even be able to harness energy to "produce" electricity which is a basic component.
Now say even if one had all the reference material it's not possible to build the facilities needed to create even one microprocessor by oneself, not to mention PCB production, etc. Now you could effectively build a PC with tubes, but you'd still require electricity, and for it to have the same power as a modern cell phone it would be such a large construction it wouldn't be possible.
I mean even with electricity it took humanity nearly a century to get where we are.