Italy has already started doing something similar with cell-tower data for people located in Lombardy. There's this article in Italian from a few hours ago [1]

Italy has already started doing something similar with cell-tower data for people located in Lombardy. There's this article in Italian from a few hours ago [1] with the president of the Lombardy region saying that more than 40% of the population (I guess that from the region as a whole, or only from Milano, I'm not so sure yet) had walked/moved for more than 300 meters outside their place of residence in the last 24 hours, all this information supposedly based on that cell-tower data I mentioned earlier. [1] https://milano.repubblica.it/cronaca/2020/03/18/news/coronavirus_lombardia_milano_notizie-251592044/?ref=RHPPTP-BH-I251519435-C12-P4-S1.12-T1 https://milano.repubblica.it/cronaca/2020/03/18/news/coronav...