Screen time 

With Screen Time, you can access real-time reports about how much time you spend on your iPhone, iPad or iPod touch, and set limits for what you want to manage

Click on this image to see how to set up Screen Time

Downtime

When you schedule downtime in Settings, only phone calls and apps that you choose to allow are available. 

App Limits

You can set daily limits for app categories with App Limits. 

Communication Limits

Control who your children can communicate with – throughout the day and during downtime. These limits apply to Phone, FaceTime, Messages and iCloud contacts. 

Always Allowed

You might want to access certain apps, even if it's downtime or if you set the All Apps & Categories app limit.  

Content and Privacy Restrictions

You decide the type of content that appears on your device. Block inappropriate content, purchases and downloads, and set your privacy settings.