Many of us rely on GPS to get around unfamiliar cities and neighborhoods, but a new type of location service could be giving you directions from the dairy section to the frozen foods aisle at the grocery store, and tracking every step you take.
It’s called IPS, or indoor positioning service, and it’s not quite as far along as the satellite service we use to find the nearest coffee shop. But the idea is the same: your phone, tablet, or maybe even your Google Glasses would be constantly tracking certain signals in your locale, from Bluetooth signals to ultrasonic beacons.
