HotCopper's mobile app was previously available on the Apple Store and Google Play; however, it is no longer supported and has been removed from the app stores. The app may continue to run on devices that already have it installed, but it will not function on new devices if they are migrated or reset, and new bugs will not be fixed. We recommend that users of all platforms visit our site in their web browser, where we continuously add new features and test functionality for mobile and desktop browser viewers.