Parental controls can be set so that children and young people cannot download an app, be added to a group chat, add a contact or access websites that are not pre-approved without the parent approving it from their device. Boundaries can be set so smartphones have limited functionality during school hours and after a set time at night.
Parental controls for Apple devices: Use parental controls on your child’s iPhone or iPad – Apple Support (UK)
Parental controls for Android devices: Android parental controls: A guide for parents - Android Authority
Parental controls for Google devices: How to set up parental controls on Google Play - Google Play Help
Online Safety guidance: Keep Children Safe Online: Information, advice, support - Internet Matters , CEOP Education, Get Safe Online | The UK's leading Online Safety Advice Resource , Online Safety Guides & Resources for Parents
Block pop-ups: guide to stop children assessing inappropriate content through accidently clocking on adverts in pop-ups – How to block pop ups in Windows - Tech Advisor
Social Media Apps
Social Media Guidance for Parents & Carers (from Police Scotland)