I use it all the time. I prefer to use this versus Apple’s iBooks. I love the cat which clearly sits near the book or item you last visited. They’ve done so good a job that the lack of English instructions don’t bother me; I can extract enough understanding from the Japanese manual. One can create folders within folders and sub-categories. I prefer their way of working so much that I had been previously disappointed that there isn’t a desktop version yet. The app has changed my mind regarding the iPad’s utility. I comprehend better how the iPad is better for books and notes versus the laptop. Arigato Tatsumi-system Co., Ltd!!
Aguilarojo about SideBooks