None of your personal data is sent to me or anyone else. Your privacy is my number one concern. When signing into music services, your username and password are exchanged for access tokens which are used to access the music service. In the event a music service does not support access tokens, your username and password are securely stored on your device in the Keychain. The Keychain is a secure part of iOS/macOS and is responsible for securely storing your login information.
Periodically, anonymized information about your device is sent to me through the use of Fabric. Things like what version of the Application you are using, the version of iOS, they type of device, and other app usage information to help provide better support. None of this anonymized information is shared with anyone else.
NO. I am a big believer in respecting the privacy of user data. I will not accept payment in exchange for your data, anonymized or not.