Parents can try any favorite parental control and monitoring software at home, but once a child (or even a spouse or grandparent) gets a data plan, I wish you good luck and hope they can speak freely during family dinners. Just as parents can choose and have the right to turn off Wi-Fi at home, they should be able to choose to turn off mobile phone signals if necessary. You cannot switch to airplane mode by holding the phone with your hand. Rotating Faraday’s cage is extreme, and only people with metal caps can try. However, you must choose to use a household battery GSM jammer whenever you need or need it.
If a jammer used in a theater triggers it within a second when the lights are dim, then concert audiences, Broadway fans, movie fans, and many others will not have to worry about such rude behavior. Of course, there are always emergencies, or there is a doctor on duty, or parents must ensure that the nanny can contact them, etc. But these people should find other ways to stay overnight.