Download or subscribe to the Math Calendar in iCal format — compatible with Google Calendar,
Apple Calendar, Outlook, and most Android / iOS calendar apps.
Use Subscribe (not download) so your app stays up to date automatically.
Geometry and Combinatorics
How to subscribe on mobile:
On iPhone/iPad, tap Subscribe — iOS will open the link in the Calendar app automatically.
On Android, copy the Download URL and add it as a new calendar in Google Calendar
under Other calendars → From URL.