I find personalized 3rd party tracking objectionable, unless the person volunteered or consented. That said, it would be quite nice to have an open API where I

I find personalized 3rd party tracking objectionable, unless the person volunteered or consented. That said, it would be quite nice to have an open API where I could query an area for the count of cell phone users active there. Of course this should have upper and lower bounds on the area, perhaps on its shape too. I emphasize that it is just count that I seek, not querying the location of a specific cellphone. Is anything like this available, free, for a fee, for specific providers ?