1,100 Technical Runbooks

Calendar Synchronization Architecture & Protocol Hub

Comprehensive engineering documentation for connecting 110 enterprise, self-hosted, and SaaS calendar systems to iPhone and iPad with zero cloud relay servers.

Unify iCloud, Google, Microsoft Exchange & CalDAV on iPhone, iPad & Apple Watch

Direct device-to-provider sync with zero cloud relay servers, live Apple WeatherKit hourly overlays, and interactive iOS 18 widgets.

Get Cloud Calendars on App Store

Visual Workspace & Live WeatherKit Overlay

Cloud Calendars Single-Day Timeline with Conflict Detection & Weather Bar
Cloud Calendars Single-Day Timeline with Conflict Detection & Weather Bar
Cloud Calendars Apple WeatherKit Hourly Temperature & Condition Overlay
Cloud Calendars Apple WeatherKit Hourly Temperature & Condition Overlay

Frequently Asked Technical Questions

What protocols are covered in this hub?

CalDAV (RFC 4791), iCalendar (RFC 5545), Microsoft Exchange ActiveSync/EWS/Graph, Google OAuth2, MDM managed configurations, and ICS webcal feeds.

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