Estimote, a company developing sensors that allow retailers to connect mobile marketing to customers' visits to physical retail locations, has received a $3.1 million seed funding, according to published reports.

The company, which makes Bluetooth-enabled beacons that retailers can use to interact with shoppers' smart phones within their retail locations, received the investment from Innovation Endeavors, Betaworks, Bessemer Venture Partners, Birchmere Ventures, Valiant Capital Partners.

Estimote is a technology start-up building a sensor-based analytics and engagement platform. They develop what they call an operating system for physical locations. The company's primary area of interest is brick and mortar retail stores, wheremore than 95 percent of transactions worldwide are still made, and where more than half of consumers visiting stores have smartphones. With Bluetooth and Wi-Fi technology, the company can build sensors that improve customer experience, bringing in new revenue streams for retail stores or cutting their costs. The company is currently piloting our solutions with the largest retailers in the United States and Europe.