Read the Docs Like a Book?

I actually don't think reading the docs like a book is efficient. I would just forget what I read, especially for those long detailed documents. I think it's better for me to locate the specific topic in the doc when I need it. I've always used Google Play Books as my epub reader in my Android devices (since it came pre-loaded in my first device) and I thinks it's pretty sufficient. I also use Apple Books in my ipad well, because it was the default one. :D And it's enough for me too. What features do you need? Why do you think these apps are limited?

Especially for big projects or services it's really impractical to read them as a book. I usually end up reading a bunch sitting at the desk while working on the thing itself, but sometimes I send a couple of links/anchor that I want to deep dive on to my phone and read them when queueing/on the bus/etc.