Google has released the statistics for the mobility and location data they gather a.o. from all the mobile devices that share their location with them. Below are the results for our region.
It shows nicely the beginning of the soft lock-down, starting with the announcement on March 12th, that from the 13th working from home was the default, and from the evening of March 15th the closure of all restaurants, schools etc. You see the enormous decline in use of transit, the drop in general retail and recreation, the drop in workplace presence due to skiing holidays and then the work from home measure, and the peak in grocery and pharmacy visits right after when the lock-down measures came into force, resulting in empty shelves in the super markets. This type of data is probably not extremely useful on a day to day basis, but it is useful to get a general feeling for how well people are complying with measures, as well as to detect the moment when things get back to their regular patterns. I know e.g. debet and credit card transactions similarly can be and are being used to determine e.g. if a community has returned to normal after for instance a hurricane or another emergency.