Available for phones and tablets that run at least iOS 9 or KitKat, Google Family Link allows parents to control the content available on their children's phones and tablets that run Nougat or later. Launched in the US back in September 2017, this service is now available in no less than 38 countries worldwide.
https://www.notebookcheck.net/Google-Family-Link-hits-27-new-markets.305116.0.html
Kids and smartphones are not a good connection for a young kid growth study says. Therefore this Family Link is not a very appealing function for a caring parent
Well, I agree that phones and tablets can turn kids into monsters sometimes (I have a daughter who will be 7 yo this summer and it's very hard to get her to do anything once she's under the spell of a tablet/phone), but services and apps like GFL at least allow you to have a certain degree of control over how, what, when your kids are doing when using their phones/tablets.