TOFU Learn is an SRS flashcard application that works on the web and on mobile. They support most languages, but have specialised in Chinese. They are often quick to fix issues when their users report them or ask for some new feature.

Features:

• You can create your own decks or use one of the pre-made Chinese decks. Among the premade decks there are three for each HSK level focusing on recognition, pinyin and writing respectively, all of them available both with simplified and traditional characters.
• You can set your review settings yourself so that you either get a test to answer (writing input and multiple choice) or you can choose to flip the cards and decide by youself how well you know that word.
• They have an intergrated Chinese dictionary so you can look up word right from your flashcard, or autofill flashcards when you create your own decks.
• In the app there is a quick-add feature that lets you add words on the go when you encounter new words.
• In the settings you can choose what kind of tone marker you want for your pinyin (or if you want bopomofo), and also activate tone coloring wich will color characters according to their tone.
• When learning a deck you can write notes for each flashcard and add an image behind each flashcard to use as a mnemonic.