Kalender Sync keeps calendars in step across Outlook, iCloud, Google and a list of German providers including GMX, WEB.DE, mailbox.org, Posteo, STRATO and kSuite. Syncs run in real time and can be set one-way or two-way, with a per-sync choice of what the other side sees: busy only, title plus time, or full event details.
A second angle is agent access: calendars can be connected to an AI assistant such as Claude, ChatGPT or Codex, which can then read and manage them on your behalf. The vendor describes the service as fully GDPR-compliant and hosted in Germany.
Plans start at €5 per month with a 7-day free trial. At the time of review the site was running a Product Hunt launch offer of 50% off a first annual year with code PH50, ending October 27, per the vendor.
