Duolingo is a free language-learning app that uses a gamified approach to make learning fun and engaging. It offers courses in over 30 languages, including Japanese, which are divided into different levels and focus on different aspects of language learning. While Duolingo can be helpful for those just starting out with studying Japanese, it should not be considered a comprehensive solution for mastering the language due its limited content. For those wishing to become proficient in Japanese traditional methods such as reading books or conversing with native speakers should also be incorporated into one's studies.