I am at the moment in which I let my children just go with the gadget, and see how it turns out. A proof of concept.
It’s impossible to implement control gadget, teach them how to, and just expect the best out of it, without correcting the parents habit, first.
It’s always the parents. Any kid’s root problem is always the parents. We fix the parents, then the children behaviour. I should learn to control my self first. My husband should do to. Then, after this, we can expect more.
An idea came. A bedtime story. Fortunately the children like it. They usually watch something before going to sleep. Tonight, we have another habit to create. Hopefully it can be consistently conducted. Ah yes. Start small, consistent, and the best result will follow.