CalSync - Local Calendar Sync

CalSync - Local Calendar Sync

Sync local calendars offline. Free, open source, no account needed.

Henrique Couto Calendar & Agenda

Screenshots

Screenshot of CalSync - Local Calendar Sync Screenshot of CalSync - Local Calendar Sync Screenshot of CalSync - Local Calendar Sync Screenshot of CalSync - Local Calendar Sync Screenshot of CalSync - Local Calendar Sync Screenshot of CalSync - Local Calendar Sync Screenshot of CalSync - Local Calendar Sync Screenshot of CalSync - Local Calendar Sync

Description

CalSync is a free and open source alternative to OneCal, CalendarBridge, and Reclaim.ai. It syncs and merges events between local device calendars — no cloud servers, no accounts, no subscription.

When an event appears in one calendar, CalSync automatically copies it to another using a name you choose. All syncing happens directly on your device. Your calendar data never leaves your phone.

⭐ FREE & OPEN SOURCE — No subscription, no hidden costs, no ads
📱 WORKS OFFLINE — No internet connection required, ever
🔒 100% PRIVATE — Calendar data stays on your device, period
👤 NO ACCOUNT — No signups, no logins, no personal info collected
🔄 AUTOMATIC BACKGROUND SYNC — Detects calendar changes within seconds
📝 CUSTOM EVENT NAMES — Choose what synced events are called (e.g. "Busy")
📋 SYNC PREVIEW — See exactly what will change before it happens
🗑️ DELETION MIRRORING — Remove an event from source, removed from target
🔄 RECURRING EVENTS — Repeat events stay in sync automatically
🎨 MATERIAL YOU — Adapts to your device's dynamic color theme

Perfect if you need to:
• Sync work and personal calendars to share availability
• Prevent double-bookings across multiple calendars
• Manage client calendars as a freelancer or consultant
• Keep family calendars in sync without sharing login credentials

If you're looking for a OneCal alternative, CalendarBridge alternative, or Reclaim.ai alternative — CalSync is the offline, private, and completely free solution.

No ads. No tracking. No telemetry. Just calendar sync that works.

Versions

Version Date Size Requires Android Download
1.9.7 current
8c65fcbd6ff60b24…
2026-08-05 19 MB API 24
1.9.7
d7e440880e005a02…
2026-08-05 17 MB API 24
1.9.7
3372d8ef78f05af8…
2026-08-05 15 MB API 24
1.9.6
a03536ee1c61eca0…
2026-07-28 19 MB API 24
1.9.6
9e39e91dfd774127…
2026-07-28 17 MB API 24
1.9.6
248eade820643f02…
2026-07-28 15 MB API 24
1.9.5
144a1853c95af935…
2026-07-10 19 MB API 24
1.9.5
9f68ef161d5dc272…
2026-07-10 17 MB API 24
1.9.5
b6aed5c95d49e443…
2026-07-10 15 MB API 24

Permissions

What the app asks the system for. Android only grants sensitive access after you confirm it.

  • Read calendarRead appointments.
  • Change calendarCreate and change appointments.
  • NotificationsShow notifications.
  • Run at startupStart automatically after the device is switched on.
  • Prevent sleepingKeep the device from going to sleep.
  • Foreground serviceKeep running in the background, visible in the status bar.
  • calsync.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION

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