It's not obvious, but if you tap on the numbers in between the << and >> where it says e.g. "23/24" to show you're on page 23 of 24 or whatever, you can type in the number of the next page. This is a horribly cumbersome workaround though, so hopefully either they fix infinite scroll soon, or better yet, nest single-page controls inside the first/last controls, like << < 23/24 > >> so that people who don't want infinite scroll on mobile can have an option too.