Compared August 2026 · every price and feature below was checked against Calendar Busy Sync’s own App Store listing on 28 August 2026. These change — check the Calendar Busy Sync App Store listing before deciding.
Free, busy-only, and it now does booking pages. Publishes little about how it works.
It is free, and it covers the busy-block case directly. Calendar Busy Sync mirrors only busy time between the calendars you pick, creating “private Busy holds… for accepted commitments” so nobody sees the details. If that is the whole of what you want, it costs nothing to try and there is no reason not to.
It also does something Calendar Mirror never will: version 1.3 added booking pages, so clients can pick a slot from your published availability. That is a different product category, and if you want it, this is the one on this list that has it for free.
| Calendar Mirror | Calendar Busy Sync | |
|---|---|---|
| Price | $2.99 once · free from source | Free |
| Platforms | iPhone, iPad, Mac | iPhone, iPad, Mac, Apple Vision |
| What it copies | Anything from a full copy down to a “Busy” block, per pair | Busy time only — “without exposing event details” |
| Booking pages | No, and not planned | Yes, added in 1.3 — with per-type booking windows |
| RSVP handling | Skip declined, unanswered or cancelled, each switchable | Holds are created for “accepted commitments” |
| Duration filters | Yes — shorter or longer than N minutes | Not published |
| Title and time-of-day rules | Yes | Not published |
| Per-event override | Yes — a tag in an event’s notes | Not published |
| Where it runs | Entirely on your device | Not published |
| Calendar providers | Anything the device can see | Not published |
| Open source | Yes — MIT | No |
None of these are coming later. If you need one of them, buy something else:
One purchase covers iPhone, iPad and Mac. Calendar Mirror is not affiliated with Calendar Busy Sync in any way, and this page is written by Calendar Mirror’s author.