Duolingo

Duolingo is an app that provides lessons in over 35 languages for those wishing to learn. It divides exercises into small, fun sessions to make it easier to absorb the information. Students can track their progress and challenge themselves with quizzes on: speaking, reading, listening, and writing. In the google play store, Duolingo maintains a 4.7-star rating with almost 12 million reviews. Overall, this is the most downloaded language app, and customers appreciate its design. All of the language courses are free, but in-app purchases are offered for Duolingo Plus. The app also sends notifications to customers if they go a certain amount of time without logging in, which has assisted with retention.