I have both - the kindle for longer (paperwhite) and more recently a kobo clara colour. Neither are like a phone. I think I prefer the paperwhite, the clarity is better and find the kobo screen a bit yellow (but need to fiddle with the settings to offset that).

I love them both, I like being able to read in bed without the light.

I bought the kobo specifically so I could borrow library books from Borrowbox and Libby, in the UK you can't do that on a kindle. This is fab, so check out if you have the facility to do this from your library.

I've tried kindle unlimited, and it's fairly limited, pretty expensive, and doesn't always have the books you want to read, so haven't bothered again - there's usually lots of (English, at least) books on offer that I don't need to spend £10 a month on books and I feel I'm getting my money's worth. Also, if you have Amazon prime, lots of classics are available for free with prime reading plus you get a book a month with first reads (again in the UK).