Privacy
Last updated 24 September 2026
Syncom is made by Athlonaut LLC. The short version: syncing happens on your Mac, your events go only to the calendars you choose, and your calendar data isn't sent to us.
What the app reads and writes
- Syncom uses Apple's own calendar framework to read and write the calendars your Mac already has. It only works with the calendars you pick for each sync.
- From those calendars it reads each event's title, times, location, notes and whether it's marked Busy or Free, within the range each sync looks at: up to 60 days back and a year ahead.
- It writes copies of those events into the calendar you chose as the destination, with as much detail as that sync's privacy level allows: full details, title and time only, or a busy block under a title you choose.
- A one-way sync never edits or deletes your originals. A two-way sync can, but only originals you own and can edit, never a meeting someone else organized.
Where your events go
A copy is an ordinary event in the destination calendar, so it goes wherever that calendar goes. If the destination is an iCloud, Google or Exchange calendar, that account stores the copy and syncs it to your other devices, as it would any event you add yourself, under its own privacy terms. Choose a busy block or title-only copies to keep details out of an account.
What we receive
- Nothing from your calendars. Athlonaut never receives your events, their details or a list of your calendars. There is nothing for us to sell or hand over.
- Your syncs, their settings and a record of which copy belongs to which original are stored on your Mac. Each copy also carries a small Syncom marker in its URL field, so Syncom can recognize its own copies.
- If you email support from Syncom's Settings, we receive that email, and a debug log only if you choose to attach one.
Permissions
macOS asks you to let Syncom access your calendars. It needs this to read events and write copies, and uses it for nothing else. You can check or withdraw it in System Settings › Privacy & Security › Calendars.
Removing Syncom
To take a sync's copies out of your calendars, remove the sync with its copies. The uninstall option in Settings removes the app, its settings and its logs.
This website
- We count visits with Umami, which we host ourselves. It uses no cookies and does not identify you.
- If you use the contact form, we receive your name, email address, what you tell us about your calendars and your message. It is delivered to us by email through Plunk. We use it only to reply and to understand who wants Syncom, and never add you to a mailing list without asking.
- The site is hosted on Railway, which keeps standard server logs. Your IP address is used briefly to limit how often the form can be sent.
Contact
Questions, or want us to delete something you sent? Email [email protected].