Safe. It is safe to download the ordinary version of the accelerated version of the school letter, which is another version of the ordinary version. School Letter Express is a mobile application service platform covering the main scenes of education, such as teaching, learning, examination, evaluation and management. It aims to build a safe and green home-school co-education bridge and help teachers improve teaching quality and personalized teaching. The latest version of School Letter Extreme Edition is a smart campus apk built by Beijing Iflytek Lezhixing Software Co., Ltd. in order to connect every home with the school.