Most language apps teach you to tap. Ether Echo teaches you to hear and speak. You listen to whole sentences spoken by a voice, and each one introduces exactly one new word. Reviews are scheduled with FSRS, the algorithm recent Anki versions use, so a word comes back right before you would forget it. Once you know about thirty words, a real-time voice tutor talks with you using only words you already know. Seven languages: English, French, Spanish, German, Japanese, Mandarin, Russian.