Mandarin Mosaic is an app that focuses on learning new Chinese words through sentence mining. The app adapts to each learner's skill level, ensuring that sentences shown contain at most one new word, making them easier to understand and retain. Features include vocabulary tracking, spaced repetition for effective memory retention, and customizable sentence packs. Users can also import external decks, such as from Anki, to enhance their study materials. Additionally, there is an in-built Chinese news reader that ranks article difficulty based on your tracked vocabulary.