Apple Watch
A customer displays his Apple Watch after buying it at a store in Paris April 24, 2015. Reuters

Apple iPhones used to be major targets for thieves, with one 2012 estimate indicating 30-40 percent of robberies in some major U.S. cities involved smartphones. During the past two years, however, Apple introduced a kill switch called Activation Lock, which can make a stolen iPhone, iPad or iPod touch useless to those who swipe it. Too bad Apple's latest pricey bauble, the Apple Watch, has no such protection.

If your iPhone is stolen with its Activation Lock turned on, your Apple ID and password are required before erasing the device or deactivating Find My iPhone. But if you want to wipe an Apple Watch, all you have to do is hold down a button. The iDownloadBlog pointed out this security flaw and posted a video showing just how easy it is to reset an Apple Watch to its factory settings.

To recap: After stealing an Apple Watch, all the thief has to do to get it ready for resale is to hold a button down and pick a few options. Usually, an Apple Watch requires a passcode when you put it on, but if you place your watch on a charger while erasing it, it will execute and bypass the passcode requirement.

That's a security flaw, and one you can anticipate Apple will address soon. Meanwhile, people wearing Apple Watches should know they may be putting themselves at risk of a robbery. Even if you didn't get the $10,000-plus gold Apple Watch Edition, your smartwatch is still a fairly expensive piece of consumer electronics, and you don't keep it in your pocket -- it's prominently displayed on your wrist.

And any thief worth his or her salt knows if you're wearing an Apple Watch, then you most likely have an iPhone on you, too.