Every book I've read over the last decade+ has been on my phone. I also use my phone for language vocab practice. For large amounts of typing though, I still prefer a computer.
My wife OTOH almost fully operates on her phone. Her phone efficiency makes me feel like a smart phone luddite hah.
I usually read tech stuff that doesn't require hands on coding to understand. At most, I just read their code examples to understand the concept. If I feel exploring it hands on will be worth while, I'll go back over it on my computer at the end of the day.
However, there are tons of great content linked from this site alone that doesn't require any hands on to understand. Get a few ebooks too, and you're set. But I'm general I don't sit on my phone a lot because I have kids, this is a 5-10 mins a couple times a day thing. Not long stretches at all.
My wife OTOH almost fully operates on her phone. Her phone efficiency makes me feel like a smart phone luddite hah.