My childhood Saturday afternoons weren't spent playing in the yard or swimming in a pool. Instead, my mother dragged me to our local grocery store, where she slowly worked her way down each aisle, matching her overflowing envelope of coupons to what was on the shelves. Ninety minutes of tedious misery, except for my one beacon of hope: an apron-clad woman who cooked samples in an electric skillet and doled them out on toothpicks. I called her Food Taster Lady. Her job was to ply my mom with coupons and to stuff me so full of hot dog bites and casserole cups that I'd beg for whatever was on offer.

These days, Food Taster Lady is being replaced by electronic beacons that beam Bluetooth signals to your phone. It's all part of an emerging "nearables" trend, in which sensor-equipped everyday objects detect your precise location, identify your personal infor­mation, and collect data about what's happening. Once you opt in, beacons deliver an enriched shopping experience, including coupons and news of special deals.

Early tests show promise. The supermarket chain Marsh partnered with inMarket--which built a network of nearable-enhanced apps--to place beacons in its 66 stores. If a customer makes her shopping list within the Marsh app, products she wants throughout the store will beam notifications to her phone or smartwatch as she nears them. Gimbal, a location-based services company, and the Miami Dolphins now target pregame tailgaters, pinging them when it's time for them to get to their seats. That system can also find fans waiting on long concession lines and direct them to shorter ones.

All of this will get more exciting once beacons are connected to the emerging internet of things, which will network data from everyday items to enable entrepreneurs to make smarter real-time decisions. For instance, beacons placed on an in-store display could report how many customers stop to look at a particular running shoe, and how many try on that shoe or merely skip over it and look at a different one instead. That data could be compared against what customers actually purchase, offering real-time feedback to the brand.

Eventually, companies could launch new products in beta just as startups do online, forgoing costly focus groups and polls in favor of testing consumer response and recalibrating before rolling out to the general public. Beacons could also track warehouse inventory, monitor showroom staff, and trace the flow of your customers.

And beacon data could be combined with other tools to find new customers. Vivanda's FlavorPrint--a sort of Pandora for your taste buds--could be paired with beacons to alert a customer that she probably won't like the barbecue sauce she's holding, but that she may prefer a different variety from the same brand instead.

The nearables ecosystem will ultimately mean the end of intermediaries: the shrinking pool of retail employees who help customers shop. Rather than trying to find an associate at Ikea, a visitor could instead summon a virtual associate for a phone chat, and ask questions about assembly or financing without stumbling over that retailer's notoriously hard-to-pronounce product names. She'd ultimately arrive at what was once the checkout stand, where a beacon would send a signal to her phone confirming her purchase, though not before suggesting any items she didn't buy but spent more than a minute considering. At the exit, she'd find a bag packed with her items, and perhaps a carry-out order of Swedish meatballs--marketed not by Food Taster Lady but rather by a nearables-powered loyalty app.

Amy Webb is founder of Webbmedia Group, which advises an international client base on emerging technologies and digital media trends.