Low-Quality Website and Poor Support
The website is almost unresponsive on iOS Safari. After every page reload it requires a new login. They don't remember the user. But you need to reload those pages when they stop to respond. The Google login is very difficult due to bugs and the login button's unresponsiveness. Unfortunately they have no mobile application, just this buggy website. The support messages may be not answered for a long time. Several times I asked to call me personally, but no one called. Then I received a letter with the placeholder "[Child's Name]" instead of my child's name. Then a teacher canceled the first lesson with no reasons explained and even no personal message. For now my experience is very poor, but I still give this website a chance.