To make calendar sharing more secure, we have a native iOS app that uses the EventKit library to fetch and push events from multiple calendars (Google, Apple, Outlook, etc) directly to your TRMNL account.
Step 0 - Get TestFlight
While this app is in beta, Apple requires testers to install their "TestFlight" app:
https://apps.apple.com/us/app/testflight/id899247664
Step 1 - Get the app
From an iOS device, visit the URL below and accept the TestFlight invitation:
Step 2 - create a Calendar plugin
Inside TRMNL, navigate to Plugins > Apple Calendar and create or update an existing instance with a "Data Provider" value of "iPhone App" at the top of the settings form.
Step 3 - Sync your calendars
Inside the iOS App, pull down on the "Sync" tab to refresh the Calendar Mappings section. Select the Apple Calendar plugin instance you just created in Step 2 and tap any calendars you'd like to be synced with this instance.
It's OK to mix and match providers. For example you could sync a personal Google Calendar and a work-only Outlook calendar. The calendars themselves will not be shared -- rather, their events will be pulled independently and synced with your TRMNL account.
Step 4 - You're done!
Going forward, calendar events should automatically sync in the background from your iPhone's native calendar app connection to your TRMNL calendar instance.
You may connect as many TRMNL calendars as you want, each with their own unique mapping and layout.
Troubleshooting
As of September 2025, this feature is in beta. Please send feedback to ryan@usetrmnl.com.