When you enter an iCalendar URL and optionally user name and password in ICSx⁵, the user name and password will be sent to the specified server and nowhere else.
User name and password for the calendars are stored in an app-private file. However, calendar URLs are accessible for other apps. If there’s sensitive data in your calendar URLs (like access tokens), don’t allow calendar access to untrusted apps!
Event data are stored by the Android Calendar Provider and not by ICSx⁵ itself. ICSx⁵ won’t send event data to anywhere.
ICSx⁵ doesn’t collect, process or transmit any statistical data like app or server usage. There are no ads and there’s no tracking.
This Web site (ICSx⁵ Web site) doesn’t collect or process personal data.
Visits are logged by the Web server. These logs are only used for maintenance purposes and to generate anonymous access statistics.