This is an open source Android app and its entire source code is available on GitHub under the Apache 2.0 license.
This app does not connect to the internet in any way - in fact, the Android operating system explicitly disallows internet access for this app in particular as it does not request the android.permission.INTERNET permission.
This app does allow the Android operating system to backup and restore its data automatically via the Auto Backup service, which involves app data being periodically backed up to your personal Google Drive account.
- For more information, see the Auto Backup service documentation and the Google Drive Terms of Service.