Smart Locks were introduced in Android 5.0 Lollipop to make your experience with your devices as enjoyable as possible.

Every once in awhile we get little surprises when new Google Play Services updates roll out to our phones and tablets, and one of these surprises was a new Smart Lock: On-body detection. This new Smart Lock is designed to keep your device unlocked — allowing the bypassing of your lock screen security — when it has been unlocked by the user and kept on the person.

With the use of the built-in accelerometer, your Lollipop phone or tablet will be able to detect movement that is then understood as it being held in your hand or in your pocket. If for any reason you set your device down, it is supposed to re-enable your lock screen pattern, PIN, password, or any other type of security that you might have enabled. In my testing, my Nexus 6 did a good job at staying unlocked when I would put it in my pocket and pulled it out after walking around for several minutes. When it came to it re-locking, I found that if my device had been lying motionless for about a minute, then it would have its lock screen security enabled when I went to use it.

Prep Work

Before you can even see the Smart Lock menu, you must first enable some type of lock screen security. To do this, head in your device's Security settings. Here you will be able to turn on a screen lock and as long as you enable any of the available options except "None" and "Swipe," you will enable the Smart Locks menu on your device.

There might be slight differences based on your device

While most of these instructions are universal, you might find some slight variations when it comes to the location of your lock screen and Smart Lock settings. The screenshots and instructions that follow are based on stock Android 5.1.1 as found on the Nexus 6. Once you have located the Smart Lock specific settings, you'll be golden.

  • LG G4: In the Security settings make sure Smart Lock is enabled as a Trusted Agent. All other Lock Screen and Smart Lock settings can be found in the Lock Screen settings.
  • Samsung Galaxy S6 and S6 edge: The Smart Lock settings can be found by going into the Lock Screen and Security and then into the Secure Lock Settings submenu.
  • HTC One M9: Smart Lock settings are found directly in the Security menu within the phone's settings just like in the screenshots provided.

Now locate the Smart Lock menu within your Security settings. You will be asked to enter your lock screen security to prove that the owner of the device is enabling the desired Smart Lock. Here you will find a list of all of the Smart Locks available to you on your phone or tablet. Select On-body detection and you will be taken to a rather colorful screen that tells you about the Smart Lock.

On-body Detection WarningOn-body Detection Turned On

When you toggle On-body detection to On, a dialog box will appear, warning you about the vulnerabilities of using the Smart Lock. The dialog also informs you that On-body detection will get better the longer you have it enabled as it will collect data on your walking patterns.

Once you have selected Continue on the dialog window, you'll have successfully turned on the On-body detection Smart Lock. The best part about On-body detection is that you shouldn't even notice that it is running on your phone or tablet except for the fact that you will no longer have to constantly unlock your device.

Should you use On-body detection?

On-body detection is a great new Smart Lock, but by turning it on, you are losing a lot of the security measures put in place by adding a screen lock. Unlike almost every other Smart Lock, there is no second form of authentication proving that the person being able to unlock the device is the actual owner. As someone who almost never lets anyone near their phones or tablets, I am secure in knowing that if I enable On-body detection, nobody else will be able to trick it and in doing so, bypassing my lock screen security. It is always a good option to weigh the pros and cons with any of these Smart Locks but with this one, it is best to look at it as only a slight step above having no screen lock at all.