More companies and retail stores are using iBeacon micro-location technology to track you.

You know that when you’re online, you leave a digital trail. That’s what tools like DoNotTrackMe are for.

But when you head offline to run errands or peruse a few stores, would you expect your every move to be recorded?

Marketers, big retail stores, and big corporations are working hard to make sure this is the case.

Your personal data and what you do in your day-to-day life are valuable to companies: it tells them how, where, and when to target you and to pitch their products. iBeacon is the latest consumer data goldmine for them, but will it be a privacy nightmare for you?

How iBeacon works

The fact that nearly everyone now carries a smartphone with them is good news for marketers. iBeacon technology relies on you having your iPhone in your pocket or purse to collect information about what you do when you shop.

iBeacon uses a low energy bluetooth signal to track your micro movement within stores (for example, whether you’re looking at the shoe display or the shirt rack). Imagine the blue dot that shows you where you are on any app that uses location (i.e. Google Maps), but with much greater location specificity.

Retailers equip their stores with small bluetooth-enabled devices that can detect visitors and track their actions through their smartphones. When aggregated, this data helps marketers to determine things like customer habits and the success of store layouts and merchandising.

iBeacon works with devices (iPhones, iPads, and iPod touches) with iOS 7 or later that have Bluetooth turned on. You can find the specifics on Apple’s site.

Where are companies tracking you with iBeacon today?

Swirl Networks, Inc. is the company at the forefront of the iBeacon retail revolution. Their customers include:

• Alex and Ani. This popular jewelry chain has plans to equip all 40 of their US stores with iBeacon technology this year. And they’re confident that it’s going to help them make more money: the company recently spent $2.75 million on a 30 second Super Bowl spot to drive more people to their retail stores.
• Timberland. Timberland, a $1.4 billion dollar apparel company with stores across the globe, has experimented with iBeacon technology.
• Kenneth Cole. Kenneth Cole has around 100 retail stores, in addition to selling its products in department stores nationwide.
• Major League Baseball. Dodger Stadium in Los Angeles and Petco Park in San Diego have both been outfitted with iBeacon.

The list will undoubtedly grow in 2014 as more companies capitalize on the opportunity to see how customers interact with their stores and products.

The dirty little iBeacon secrets: what Apple won’t tell you

What you’ll see: In some ways, the technology will make its presence known to customers. People entering stores with a smartphone may receive a notification, such as a thank-you or an indication of current promotions. The technology could also direct customers to sales and sections within the store, or send customers targeted notifications depending on what section of the store they’re browsing. Walking past the scarves? Here’s a push notification.

What’s beneath the surface. The reason marketers are in hot pursuit of this tech advancement is because of its ability to track customers’ slightest moves. The technology allows indoor, micro-location tracking throughout a store for “hypertargeted content delivery,” according to Swirl’s website. But while companies frame the technology as a service to customers, showing them deals and helpful shopping hints, iBeacon technology is a two-way information street: what the company really wants is to collect information about you.

The fact that you have a iPhone now opts you in to be tracked, and opting out may prove complicated, as Ben Isaacson explains in a post about iBeacon opt-out.

iBeacon follows a common theme in recent marketing technology: less oversight and control of when and where your information is being tracked.