Elfinbook re-writeable notebook. Elfinbook is made of stone paper. It is waterproof and durable. It can be used repeatedly with an erasable pen. Because the content disappears after erasing, we have developed a supporting APP for this notebook to save notes. The software uses machine vision and image processing algorithms and automatically After you find the border of the book, you can crop and straighten it. You can also choose a variety of image enhancement effects. Elfinbook supporting APP has a powerful document management function. It uses Windows tree file structure for classification management. At the same time, you can search and easily find the paper materials you wrote. In addition to powerful local file management functions, it connects to most common clouds, and can generate PDF files for uploading to the cloud with one click, such as Evernote, Baidu Cloud, etc., no longer afraid of losing notes, where to see where you go.