Shazam is a very handy app. You no longer have to spend hours racking your brain to remember the name of a particular tune. For years now, people have been able to just pull out their phones and Shazam will identify the mystery melody in seconds.

More recently, the app has allowed you to easily purchase said music in just a few clicks. It's a useful tool rather than an essential one, but the Apple Watch could change that.

Shazam uses the mic on your smartphone to detect audio in your environment. But since your phone spends most of its time in your pocket, opportunities for listening are limited. However, with the Apple Watch, Shazam could be always listening, and capturing valuable data about users which could be used in a multitude of ways. If you walk into a store, Shazam could detect where you are and give you a list of sales and special offers.

"It's all part of a vision into the future, which is that Shazaming will become seamless, simpler, and an integrated part of your life," Shazam chief product officer Daniel Danker told the International Business Times. "We keep saying, 'What could be easier than touching a button?' Well, not touching a button."

The company has already made moves in this retail space. In November in partnership with Mood Media it launched Shazam In-Store, which picks up on Mood Presence, a kind of ultrasonic signal that is inaudible to humans but which can trigger phones and apps to take actions when they detect them. This is already rolled out in Office Depot outlets and a further 175,000 retailers use Mood Presence signals.

Shazam has also partnered with Gimbal, a company which installs Bluetooth beacons in outdoor locations which would allow advertisers to sell directly to smartphone users in their vicinity.

It's a little creepy to think that your watch will be spying on your daily activity like this. While we've become accustomed to the idea that everything we do online is tracked, we assume that once we put our devices down, the tracking stops. I guess you could always just turn the always-listening option off, but then that might defeat the purpose of the smartwatch. The entire use-case of the smartwatch and wearables general is that they are always on, and feeding us information at a glance. After all, if we have to go looking for information we may as well pull our phone out of our pocket.

The Apple Watch won't quite send us diving head first into a world tracking our every move like the one in the 2002 Tom Cruise movie, Minority Report. Shazam can identify any song it hears because it has deals with the record companies. For Shazam to be able to detect where you are it would have to make individual deals with all the retailers emitting these ultrasonic signals. Apart from the logistical difficulties involved, many of these retailers might not want a third party controlling which ads are sent to its customers.

It's certainly an interesting use case for the Apple Watch, though. For the millions of Apple fanatics unwrapping their watches today, they might want to stop and consider for a moment that they may be slipping an advertiser's dream onto their wrist.