CalCollapse
Collapse your Google Calendars and webcal feeds into one iCloud calendar you already have, so everything you have committed to shows up in Apple Calendar in one place — on your Mac, your iPhone and your Watch.
What it does
Reads the calendars you pick
Connect one Google account or several, and paste any webcal or iCal subscription — TeamSnap, ParentSquare, a secret Google iCal address, or anything else that publishes one. For each source you choose what to read; nothing you have not paired is ever touched.
Writes them into a calendar you already own
You choose an existing iCloud calendar as the destination. CalCollapse never creates, renames or deletes an iCloud calendar, and it only edits the events it wrote itself — anything you added by hand is invisible to it.
Keeps them current, within the minute
Changes usually reach iCloud within a minute of you making them, and every 15 minutes regardless. You can also trigger one yourself at any time. Every run is logged with what it moved, so a sync that fails is visible rather than silent.
Goes one way, on purpose
Events flow from Google or a webcal into iCloud and never back. Editing a synced event in Apple Calendar will not push to the source — it will be overwritten on the next run.
What we do with your Google data
CalCollapse requests three Google scopes and no others. None of them can write anything to your Google account, and each is here because a specific part of the app stops working without it:
openidIdentifies the Google account you are connecting, so we can tell your connected accounts apart.https://www.googleapis.com/auth/userinfo.emailReads that account's email address, so the account is labelled with something you recognise rather than an opaque id.https://www.googleapis.com/auth/calendar.readonlyLists the calendars on the account, so you can choose which to sync, and reads the events on the ones you chose, so they can be copied to iCloud.
That is the whole of it. We request no scope that can write to Google, so nothing in your Google Calendar can be created, changed or deleted by this app even in principle — and we ask for nothing outside Calendar at all: no mail, no contacts, no files.
Your events are stored so that each run only has to fetch what changed since the last one. They are deleted when you delete the calendar pair, disconnect the account, or delete your account. We do not sell your personal information, and nothing in your calendar is used for advertising or shared with anyone else. The full detail is in the privacy policy.
You can withdraw the access at any time, either by disconnecting the account here or by removing CalCollapse from your Google account permissions.
Getting set up
You sign in with Apple, connect iCloud with an app-specific password, then either connect a Google account or paste a webcal URL, and pair a calendar with a calendar. The walkthrough shows every screen before you hand over anything.
Trying to get Google Calendar onto an iPhone? Copying Google calendars into iCloud is the whole of what this does for Google. The name is the job: a cal collapse is several calendars becoming one iCloud calendar you already have.
Syncing a work calendar? Google Workspace calendars work the same way, with the read-only access and the absence of invitation emails that a shared work calendar needs.
Sitting on a pile of webcal subscriptions instead? Copying webcal feeds into one iCloud calendar is the other half of the same job — TeamSnap, ParentSquare, or any feed that publishes one, written into a calendar you already have rather than added as yet another subscription in Apple Calendar.
Trying to get a team schedule onto an iPhone? Sync TeamSnap with iCloud. A school calendar? Sync ParentSquare with iCloud.
Comparing this against a paid sync tool? How it differs from OneCal covers what you give up by choosing the smaller thing, as well as what you stop paying for.
Arrived here from a scheduling tool? How this differs from Calendly — booking links and calendar sync solve different halves of the same complaint, and this is the sync half.
CalCollapse is operated by Watts Life Technologies, LLC.