Monday, June 30, 2014

Android Device Manager can locate a lost phone

How to: Android Device Manager can locate a lost phone and optionally can erase all data.  Updated 2014.07.

What to do if you lose your Android device?  Google provides a free service that works reasonably well, with some restrictions.

If lost, use this process before the device's battery gives out.  You should experiment with this once, prior to losing your phone to make sure everything works as expected. 

If you know the phone or tablet was stolen, you can use this service to wipe the device, provided you prepared for this ahead of time.

 Find the Device

1.  On your Android device, open Settings, Locations.  Enable "Google Location Services"  (This service is required and must be enabled prior to losing your phone.)

2.  Launch Android Device Manager by opening


3.  Login with your normal google/gmail account.
(This account is a given; you had to have an account in order to setup your phone on the Android App Store.)

Note: If you use Google's two-stage authentication (see this keyliner article: hack-proof Gmail), a second authentication code will be sent to your lost phone, which will not help you.  Use the emergency access codes when two-factor authentication was setup. 

4.  Once logged in, the map shows the approximate location of your phone.  If you own multiple devices, select your device from the pull-down menu.  The device must be on in order to calculate a location.

The webpage may prompt "Remotely Access this device?"  This can be enabled from the web-page without physical control of the phone -- but you must have Location Services enabled (step 1) prior to this test.

5.  Presuming you have already called the phone to see if a good Samaritan answered, click "Ring" and the phone will ring at its loudest volume for 5 minutes, regardless of the current volume setting.

With the indicated location, drive there and wrestle the phone from the person who found it.


The service actually sends a message to the device and that means it must be connected to either the cellular or on a wireless Internet.  If both are turned off, or the phone is powered off (dead battery), you will not be able to locate the device.  Prior locations are not cached.

Accuracy with a wireless network appears to be about 25 meters (roughly the range of a wireless antenna).  If the phone is only on cellular, accuracy falls off to within 2000 meters (at least in my testing).  It did not appear to triangulate off multiple cell towers (in my area, there is only one near-by tower). 

Naturally, for my Nexus 7 tablet, wireless is the only option -- and if it is turned off, you will not be able to locate the device.

Finally, at my office, location requests are apparently blocked by the internal routers and no location data was available for any of my devices while in that building.  I have not thoroughly tested this issue. 

Wipe the Device

To remotely wipe the device, you must enable the feature and you must have physical access to the device prior to losing it.  In other words, do this now; there is no harm.

A.  From the device, open the All Apps menu (showing all applications installed). 
Open the "Google Settings" program; on newer Androids, this icon is grey.

B.  Choose either "Android Device Manager" (on older devices) or "Security"

C. Select "Allow remote factory reset"

D.  After wiping the phone, contact your phone carrier and have them disable the device from their end.

Missing Features

While all of the features on Android's Device Manager are well-and-good, there are some things this program should be able to do, but does not.
  • You should be able to set a keypad-lock on the login screen (you don't already have that set?), or change the current keypad lock number.  [Update: Starting 2013.09, Google now allows you to set or change a PIN, even if one was not set previously.  However, in order to use this feature, you must enable the "Allow Factory Reset", as described above. 

    This brings up an interesting idea.  You could disable the keypad/pin unlock on your phone, making the phone easier to use on a day-to-day basis and then, once the phone is lost, you can dial-in and setup a PIN as-needed.  But keep in mind, you can only do this if the phone is turned on and you are watching on these screens, making this a risky option.
  • You should be able to take two photos, one with the front-facing and another with the rear-facing camera, and have them sent to your email address the next time the phone turns on.
  • If the device is turned off, you can't issue a request to find its location the next time it turns on.  You have to be in the Device Manager website in real-time. 

Other things to do:

These suggestions are not part of the Android Device Manager, but should be done regardless.  Take steps to secure your phone and give honest people the ability to return the device, even if the battery is dead.  Here are my suggestions.

As big of a pain as this is, turn on the device's keypad lock screen and enter a key-code each time you turn on the phone.  Use at least a 5 digit pin.  Also, set the keypad timeout delay to 15 minutes, which makes this feature more tolerable. (Update:  I have recently turned on facial recognition and it has worked well.)

Without an unlock code, anyone with your phone has unfettered rights to your email, documents and the address book.  For example, on my phone, they could adjust the thermostat in my house, edit this blog, order movies on Netflix, change my newspaper subscription and buy movies and music.  In other words, pranksters would have a good time. 

If you have an older phone, open the battery compartment and leave a note telling them an alternate number they can call.  Obviously, do not use your own phone number.

On my smart phone, I used one of these slick label printers and printed an alternate number on the back of the phone.  I bought a black-text on clear background label so it looks professional.  This has actually helped to recover one of my lost phones. 

If your device allows, add a message to the lock screen, "Call if found".

Find lost phone location services

hack-proof Gmail,