This app is a companion app for Chat Master speakers. The app uses Bluetooth to communicate with the speaker. When you open the app for the first time, in the Bluetooth dialog box, please allow the use of the Bluetooth function. The user registers an account through the email address to complete the login. Users can add or delete multiple Chat Master speaker devices, set WIFI for the added devices, and choose the dialogue language with the speakers. When these settings are completed, we can happily chat with the Chat Master smart speaker.