I don't have information at what age a child in Serbia gets their first mobile phone, nor at what age do all children have their own device. It is safe to say that this happens in the lower grades of primary school and that we are getting closer to starting school becoming that turning point. The next important moment is entering the upper grades of elementary school, the seventh and eighth, in the teenage years. Then the problems begin. You call, and the child doesn't answer you because he has "more important things to do" and you (a caring parent) suddenly become a jerk. In high school, when late night outings and other types of challenges begin, this relationship becomes more severe, i.e. the number of parental calls to which there is no prompt response increases.
Threatening to confiscate your phone is pointless. The child will still do what he wants, but you will be left without the communication that you consider necessary. That's why a mother in America came up with the mobile phone app "Ignore No More" (ignorenomoreapp.com), which is now getting a lot of attention.
The essence is that parents use the application to create a family virtual network in which they include children. Parents are administrators, and since they buy mobile devices for their children, they have the opportunity to install this application for them.
Its meaning is that the child must respond to the parental call. If he ignores it, the phone is locked and the only thing he can do is call the numbers that you set for him and put in the priority list (emergency services are mandatory). He can't even send messages to others, the device is practically dead. The parent can unlock the phone (with a message) if he deems it necessary or give the child a password. The same applies to locking, it is possible to do it from a distance and wait for a tempted or angry cub to call you.
All leading operating systems are supported, and most of the questions that come to your mind will be answered on the site that supports the application.
I don't think you need to explain that teenagers are disgusted by this app unlike their parents. But I can imagine that parents will soon choke if their boss at work thinks that this (or similar, slightly refined) application could be used for networking business phones.
In that case, employees could use the official phone when their superior allows them and only for numbers specified by him (including incoming calls), and he could force them to answer, prevent them from turning off, get information about the state of their battery, so that they could not convince him that it was empty, so they were excluded. This means that the phone becomes a remote control only when you become a device whose behavior is controlled by someone from afar.
Because if parents are allowed to supervise their children in this way, there is no reason why it should not be applied to others as well. Or to regulate it legally, before it expands dramatically.
I imagine a wedding of the future where instead of rings, newlyweds in love click YES on software that asks them to confirm that they can control each other's phones in the future. Until the operator takes them apart.