The courses are available on Android, iOS and the web.

Whether or not you need to know Arabic, this marks an important milestone for Duolingo -- it now teaches the five most commonly spoken languages on the planet. You can generally assume that Duolingo will help you settle in a new country or make your next vacation slightly less intimidating. The service still isn't as flexible for non-English speakers (Arabic speakers can only learn a handful of languages). This is, however, a step in the right direction.