Integrating with Apple iCal - Export
ActivityTimeline add-on allows integrating a person's timeline with Apple Calendar. To build one's timeline into Apple Calendar, follow the steps:
Navigate to My Account in ActivityTimeline → Calendar Integration tab.
Click on the Renew Calendar Link to generate a unique iCal Datafeed URL.
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Open your Apple iCal application.
Click on File → New Calendar Subscription
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Paste the previously copied URL into the blank field and press Subscribe.
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Name the new calendar & set the Auto-refresh period to Every hour and click OK.
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JIRA tickets and custom events that are scheduled on a person's timeline should appear in the Apple Calendar application.