How to set up and use Screen Time on iOS 12

iOS 12 is designed to make your iPhone and iPad experience even faster, more responsive, and more delightful.

Screen Time

New tools empower you to understand and make choices about how much time you spend using apps and websites.

After updating to iOS 12, the Settings app will have a new section titled Screen 

How to Activate Screen Time

Open Settings > Scroll to Screen Time which in next to Do Not Disturb > Once you Tap the screen will ask you for First Time is this iPhone/iPad for yourself or your child? > the it will ask for Downtime.

For kids

Use your family’s Apple IDs to set up Screen Time for your kids to keep an eye on how much time they spend on apps and websites. They can request more time for you to approve.

Activity reports

Get reports weekly or check Today View anytime to see app usage, notifications, and device pickups.Time.breaks down usage for the current day, as well as the past 7 days. Screen Time will also break down how often you pick up your phone, which apps you used the most after picking up your phone, and how many notifications you receive on a per-app basis.

Downtime

Set a specific time, like bedtime, when apps and notifications are blocked. You can choose which apps are on and off limits. 

Always allowed

Create exceptions for apps you’d like your kids to have access to even during Downtime, such as Messages or education apps.

App limits

Set the amount of time you and your kids can spend each day on specific apps and websites.

Content & Privacy Restrictions

You can block inappropriate content like iTune & App store purchase, Privacy and also block change of passcode changes, mobile data changes.

You can also set Screen Time passcode :

Open Screen Time > Scroll down below Content & Privacy Restrictions > Use Screen Time passcode > Toggle the switch to green and set passcode.

you can also enable combined screen time which are signed with the same icloud id. also setup screen time for Family.

To turn off screen Time

Open Screen Time > Scroll down below  >Turn off Screen  > enter passcode (if setup). 

https://www.apple.com/ios/ios-12/features/