How to Unlock Your Samsung Galaxy S3 with NFC

Having a password, PIN, or combination lock on your device can be quite an inconvenience every time you want to unlock your phone, especially when you have one for the sake of guarding against snooping eyes. If this is the actual case for any of you Samsung Galaxy S3 users out there, you may be pleased to know that you can bypass this problem while maintaining the security with the help of NFC tags.

Monteillard has come up with a sneaky way of making this possible on your GS3 for rooted users with Tasker, WidgetLocker, and NFC Re-tag, all of which can be found on the Play store. Users must flash a specific mod that’s available for download, setup WidgetLocker with the ‘unlock’ function, create four profiles with specific settings laid by Monteillard, and then add your NFC tag with NFC Re-tag with a couple of required settings to get things started.

The advantage of this mod is that you’ll now be able to unlock your phone with NFC tags and bypass the security screen, while maintaining the security that you have with your password, PIN, or combination lock when others get their hands on your GS3. There’s no restrictions on which NFC tag will work, as generally anything with NFC, be it textiles, NFC stickers, cards, or tags, will be compatible. Owners of other devices may be able to get this working, as one such user with a Sony Xperia S has done so successfully. However, the fact that you must flash a GS3-specific mod through recovery may mean otherwise for most.

here is a tutorial on how to use a nfc tag to unlock galaxy s3 and other android devices with nfc.

Translated from the french version : http://www.galaxys2.fr/forum/voir-t14883.html#p146889

Required:
-Anything with nfc (nfc card , nfc tag , tectiles ...)
-Be rooted
-Installed Tasker + secure settings plug-in , Widgetlocker , NFC Re-tag
-download the NFCmodSGS3_lockscreen matching your ROM here : http://pc-updates.blogspot.com/2013/06/nfc-with-screen-lockedoff-update-for.html
-Deactivate any lockscreen in settings (even the slide to unlock one)
-10 min of time

Ready ? Let's go

Step 1 : Flash the NFCmodSGS3_lockscreen***** via CWM


Step 2: Lockscreen configuration

Start widgetlocker and select a lockscreen with only one function : unlock


In settings , inputs, enable the back button, in advance select the 2 last ones 

Step 3: Tasker

New profile :
events, 3rd party widget locker , unlocked ==> if %WIFI~Off, wait 300ms , plug in secure settings password pin , enable : type the password you want to use if you forgot your nfc tag.

New profile : 
event, display screen off ==> plug in secure settings nfc on

New profile:
event system boot : plug in secure settings password pin , enable : type the password you want to use if you forgot your nfc tag + condition %WIFI~Off

New profile:
event network , wifi on , plug in secure settings password pin , disable
Exit task : plug in secure settings password pin , enable : type the password you want to use if you forgot your nfc tag.

New task: (name it UNLOCK)
plug in secure settings password pin , disable
wait 200ms
input , button : back button

Step 4 : NFC-Retag

Scan your tag and add the action : tasker task : UNLOCK
In settings , mute pop ups et do not show


 And you are ready to go ! 

Video in french on the original thread, feel free to correct my mistakes or help me improve the way this tutorial is (it's my first one)