To set an event reminder

Tap an event to view its details.

If no reminder is set, tap to automatically add a reminder for 10 minutes before the event.

Tap the Time field to set the length of time before the event that you want to be reminded of it. Tap the Notification field to set how you want to be reminded (by Notification or by email).

When the time comes, you receive a notification about the event.

You can use Google Calendar on the web to configure additional reminder settings.