>Google Maps does that. Search for a popular cafe on your area and you should see the "Popular times" graph with live data. Google also sends local businesses

>Google Maps does that. Search for a popular cafe on your area and you should see the "Popular times" graph with live data. Google also sends local businesses a Bluetooth Beacon to install on the ceiling inside their business to help with with getting the "popular times". It's called Project Beacon and any local US business can request one. http://g.co/beaconhelp http://g.co/beaconhelp "Project Beacon is designed to improve the performance of location-related features in Google products for your venue, such as popular times, reviews etc. The beacon itself is configured for just this purpose, and isn't re-configurable by the user. If you would like to obtain a beacon to use with our developer platform, you can find a list of manufacturers at g.co/beacons"