Unless you live under a rock, you've heard that Google (GOOGL 0.35%) is buying connected device maker Nest for $3.2 billion. However, what you might not know is how Google could use Nest's products in the future to track your every move. The search giant, after all, is known for its proficiency in collecting and mining user data. And what better way of doing this than through in-home devices such as Nest's smart thermostat or smoke detector?

Acquiring Nest gives Google an entry into the burgeoning "Internet of Things" -- a market that's expected to be worth $14.4 trillion over the next decade, according to Cisco. If you're not yet familiar with the term, it refers to the growing network of machines, appliances, and everyday objects, which are being connected and controlled through the Web today.

Tracking how you live
Nest's devices take home automation to the next level by actually monitoring a users routines. The company's smart thermostat, for example, uses auto-away technology to detect when you leave the house. It then automatically adjusts the temperature to avoid heating or cooling an empty home. While this seems useful, some people have concerns over the privacy implications of such products -- particularly now that Google will have access to the information stored by Nest products.

Nest's founder, Matt Rogers, was quick to counter this argument by pointing out that the company's privacy policy "limits the use of customer information to providing and improving Nest's products and services." Even so, privacy advocates need to understand that Google already has access vast amounts of personal data by way of its Android operating system.

In fact, using location services Google knows the precise position of every Android-user's WiFi enabled device. That's especially important, considering ABI Research estimates that a whopping 798 million people use Android-based mobile devices today. Of course, the same goes for Apple (AAPL -0.57%), which currently counts around 294 million people as iOS users today, according to similar research. While Google and Apple say they don't share such data with outside companies, a new industry is emerging today with the sole purpose of capitalizing on such information.

Big brother's nosey siblings
Meet Turnstyle Solutions, a consumer analytics company that uses location based services and WiFi to track your every move. A recent story in the Wall Street Journal documents how this company can use strategically placed sensors to track your smartphone's WiFi signal. Turnstyle can then use this information to create detailed profile's on people's habits, which it in turn sells to nearby retailers and businesses. For consumers, this technology can become intrusive. However, for retail stores, location data provides valuable insight into consumers' shopping habits. Even Apple is jumping on the bandwagon these days.

The Mac maker launched its iBeacon short-range positioning tech at 254 of its U.S. stores in December. Using Bluetooth low-energy, or BLE, Apple's iBeacon is able to send notifications to customers' iPhones as they shop in an Apple store. For example, Apple can push messages to your phone about specific product offerings or let you know where to go to pick up items you ordered online.

Importantly, iBeacon also works with Android devices. This could make it even easier for retailers of all sizes to leverage Google's massive Android user base. As more items become linked to Google and Apple devices, these companies are able to collect an ever-increasing amount of data on the way people use such objects. Ultimately, Google wants to own the future, and with strategic acquisitions like Nest and Android's growing share of the mobile market, it just might.

How Google will use the information it collects on us only the future will tell. Of course, you can always turn off your Wi-Fi, if you'd prefer that Google or a company like Turnstyle not track your movements. Still, in today's hyper connected world that's often easier said than done.