How to Add Notes to iPhone Calendar Events
Adding a URL and a note to an event on your iPhone Calendar is a great way to remember things associated with that event without having to store the information somewhere else.
If you're scheduling a video conference or a webinar attendance, adding the URL for the call gives you instant access at the scheduled time and add any other useful information about the appointment in the Notes field, such as the phone number of the person you're going to meet or the confirmation number for a flight. To add a URL and/or note:
Tap URL on the Add Event screen, or Edit screen if you want to add to an event you already created.
Type the URL.
Open Safari and go to the web page you want to add to the event, tap and hold in the URL field, copy the address, and then switch back to Calendar. Tap and hold the URL field and paste the copied address.
Type in the information you want.
Or copy and paste to the Notes field from a contact, website, note, or an e-mail: Switch to the app that contains information you want to copy.
Copy that information. Double-click the Home button to see the open apps and tap Calendar. You return to the Notes screen where you left off. Press and hold in the field until the magnifying loupe appears. Lift your finger, and then tap Paste. Voilà The information you copied is now in the note of your event.