TiviBoy has no user accounts. The only data associated with your device is anonymous usage statistics (Firebase Analytics) and, if you enabled notifications, a push token (OneSignal). Your playlists, credentials, favorites and watch history are stored only on your device and are deleted completely when you clear the app's storage or uninstall it.
Email devkoi@proton.me with the subject "Data deletion request". Because analytics data is anonymous, please include your Firebase App Instance ID if you can find it (or simply tell us the approximate dates you used the app and your device model), and we will delete the associated analytics data via Google's User Deletion API and remove your push subscription from OneSignal within 30 days.
Local app data on your device is under your control: clear it any time in Android Settings → Apps → TiviBoy → Storage, or by uninstalling the app.