Only the current version so far — new entries appear as the app ships updates.
Youtor–背單字、線上測驗、會話口說、VRP虛擬點讀筆 is a books & reference app by I'M Integrated Communications Ltd with 100,000+ downloads (about 141K estimated). +355 installs in the last 7 days. Released Aug 3, 2018. Install growth, rank history, SDKs and ad networks.
From the store listing: “The language learning system that understands the brain best, choose a variety of interactive modes, and learn foreign languages easily and painlessly!”