Company Jumpei Adachi created these great apps:
Learning Rhythm, Soroban Training, 和音音感トレーニング, リスニング暗算, Piano Chord Memorization, IPA Ruby, Pinyin Extension, Furigana Browser Extension, 履歴カウンター, Images Comparison, 旧字体拡張, PlaneNotes, ノビのび日記, and others..
