To turn Anti-Phishing Warnings on or off, go to
Settings > Safari
and then modify the settings for Fraudulent Website Warning. When Anti-Phishing is on, Safari will alert you when a site you’re visiting *may* be a phishing site.
Here’s how to silence alerts from shared calendars on your iPhone or iPad:
You will find a setting for notification sound and other ways to configure shared alerts in this settings:
Settings > Notifications > Calendar > Shared Calendar Changes