This is a concern by itself, but what made matters more serious was that selecting Settings > General > Reset > Erase All Contents and Settings would completely wipe the device, enabling a thief to easily sell it on.
Apple has fixed this latter flaw, although the ultra-security-conscious should know that it's still possible to briefly check the contents of the Apple Watch using the sensor trick - at least while they're still in range of your iPhone. Spies and civil servants might want to worry about the loss of any vital data on their smartwatch, but the rest of us don't really need to worry on this account.
Apple Watch passcode and the Watch OS 1.0.1 security update
Apple has issued a recent update to the Apple Watch that fixes the sensor security flaw. We updated to Watch OS 1.0.1 and tested it out. The Apple Watch now requests the four-digit passcode to perform a wipe & reset regardless of whether it's being worn or not.
Prior to the Watch OS 1.0.1 update we were able to remove an Apple Watch from somebody's wrist and reset it without knowing their passcode. We can't now repeat this trick.
Apple's clearly moving fast to prevent a "Watchgate'" incident from forming.
Is it possible to crack an Apple Watch passcode?
At the moment we know of no way to crack the four-digit Apple Passcode, although we imagine security experts are testing it. The Apple Watch does contain a hidden 6-pin diagnostic port underneath the strap. This may enable nefarious souls (or more likely, forensics experts) to connect to the device and crack the passcode.
As far as we know, there is no software available that can bypass the four-digit code on an Apple Watch, although it's only a matter of time. This software tends to be highly regulated and is hard to get hold of. Also, you have to be highly skilled to use it (it's not a common fate for stolen Apple devices to be hacked).
If you are particularly concerned then choose a 10-digit passcode. This will be much harder - practically impossible, even - for a cracker to get past once they have your Apple Watch.
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