I'm a bit torn about the Long Earth series as I find them a little frustrating whilst still dragging me in. I don't feel it's wasted time for me, so they have something. I don't think I've read any of Baxter's own books.
I read books on my phone that are mostly from the Google shop. I have bought some from Humble Bundle and imported them into Google for convenient reading. I don't have a dedicated e-reader, but my daughter has a Kindle. I've heard good things about Calibre.