Apple's tastes run almost exclusively to best-sellers, and even among them there are some odd omissions like Michael Lewis's The Big Short. There are no listings, for instance, for Ludwig Wittgenstein, Martin Heidegger, Wallace Stevens, Irving Kristol, Reinhold Niebuhr, and Walter Lippmann. By contrast, the Kindle offers 49 listings for Heidegger, including Being and Time; 80 listings for Wittgenstein, including several versions of the Tractatus Logico-Philosophicus; one book by Irving Kristol and an anthology that includes his writings; three books about Wallace Stevens; one collection of Niebuhr's writing and a work about him; and 19 books for Walter Lippmann, including six books by him.