Only the current version so far — new entries appear as the app ships updates.
化学ドロップ（中学高校）・覚えよう元素記号 is an education app by PotatoTime with 1,000+ downloads (about 1.8K estimated). Released Jan 24, 2014. Install growth, rank history, SDKs and ad networks.
From the store listing: “Chemical symbol that you memorize. Is a junior high school science for learning app.”
