One of the most popular free language sources, Duolingo offers fun, bite-sized lessons of Portuguese. 5 minutes a day is supposed to be enough to develop solid reading, writing, and speaking skills. It is easy to use and it feels like you’re playing a game. Unlocking new levels and earning virtual coins keeps you motivated and, if we are to believe to the authors, 34 hours of Duolingo are equally valuable as one semester in the university. While fun and free, serious students would benefit from looking elsewhere. Read our full review of Duolingo Portuguese.