Caltsu

Sync Google, Outlook & Apple calendars. Keep events private.

You run work on Outlook and life on Google Calendar. Maybe three client accounts plus personal iCloud. Either way: double bookings, leaked event titles, your dentist on the team calendar. Caltsu syncs busy/free times across Google, Outlook, and Apple calendars—bidirectionally, in real-time—without copying event details between accounts. Two-minute setup. Runs silently in the background. Free: 2 accounts, one-way sync. Pro (€7/mo): 10 accounts, unlimited rules, webhooks, bidirectional.