Just a few weeks ago, Apple teased its new iBeacon location technology for mobile devices in its own retail stores. Now mobile marketing company inMarket has announced a program to let grocery stores use iBeacon to send content to customers’ mobile devices when they’re walking around stores.

With inMarket’s Mobile to Mortar service, grocers can serve reward opportunities to shoppers, remind them of items they might like to buy, and display shopping lists, based on shopper location. The service will operate in more than 150 grocery stores in Cleveland, San Francisco, and Seattle, with more stores targeted for rollout in the months to come.

Mobile to Mortar takes advantage of iBeacon’s low-power BlueTooth technology, which in turn depends on “a virtually invisible beacon the size of a quarter” to transmit the location of mobile devices. That’s a smaller implementation than some other iBeacon transmitters. The iBeacon protocol differs from more traditional latitude- and longitude-based location systems.

“Besides Apple themselves, we are the first to take this groundbreaking technology out of beta tests and into consumers’ lives throughout the heartland of the US,” inMarket cofounder and chief executive Todd Dipaola said in a news release.

inMarket has a shot at being remembered as being early to commercialize iBeacon. The pertinent question is, how much of a difference will the service make to retailers?