Duolingo launched Stories as an experiment, as its team points out in an August update, so they aren't sure when (or if) they'll add more languages. Expanding up to four is a good sign, though, and shows promise for the service's experiments beyond typical lessons. Earlier this month, Duolingo launched a podcast focusing on Spanish-language non-fiction stories, which can be found on iTunes, Google Play Music, Spotify and elsewhere. Stories remain on the Duolingo site, but as it's still in beta, they don't add XP for participating -- they're just for your own learning pleasure.