Im thinking like an micro chip implanted in our body. This system is not out of the picture because how we discover things every year, it is not impossible that in the future this things may happen and it will boom like btc.
It is possible, however, against the background of the fact that there are so many prerequisites in cinema and world culture that chipping people eventually lead to complete total control can cause difficulties. People don't like being manipulated. Of course, this can be done under the sauce of promotions or bonuses, but still should be an alternative for those who do not want to implant a chip under the skin.