What is the best cross-platform approach to blocking websites?

Maybe there is none, and I have to just do it separately on each device. I have a few websites that I would rather just cut from my life completely.

My assumption is that I should push a hosts file to github and clone it on each device I use?

That would be ok for windows, ubuntu and mac. But what would I best do for a non-rooted android, or an iphone?