Only the current version so far — new entries appear as the app ships updates.
メモ帳 - がんばれ!ルルロロ is a tools app by RedinC with 10,000+ downloads (about 18K estimated). Released Dec 2, 2013. Install growth, rank history, SDKs and ad networks.
From the store listing: “Very popular among the girls! Cute notepad app "Ganbare! Rururoro"!”