This calendar can display the following types of holidays.
1. Turn on a subscribed holiday calendar under "Display Settings"
You can change the color of a subscribed holiday calendar (for example, "US Holidays") from the settings screen in Simple Calendar.
Steps
1. Tap the gear icon (Settings) at the top right of Simple Calendar.
2. Tap "Add/Edit Calendar".
3. Tap the holiday calendar.
4. Choose the color you like under "Label Color".
5. Tap the checkmark at the top right (on iOS 18 or earlier, tap "Done") to save.
2. Turn on Google Calendar holidays in "Display Settings"
If you want to change their color, change it in Google Calendar.
If you want to hide them, find the calendar in the app's "Display Settings" list and turn it off. Tap the calendar to show or hide it.