Here's a video demonstration of what the process below enables:
What you'll need:-A rooted Android phone with the NFC service modified to allow for constant polling and tag removal detection.
-A modified version of AnyTAG NFC Launcher
-Secure Settings with the Helper installed
The first step will be to find a modified NFC apk for your phone. There are many modified NFC apks that allow for polling while the screen is off, but you might have trouble finding one for your phone that allows detection of tag removal. Details of the modification procedure are outlined in the XDA thread above. If your phone can't detect tag removal, you won't be able to automatically relock the phone when it's taken out of your hand.
Once that's done, install the modified AnyTAG NFC Launcher application, Tasker and Secure Settings.
1) Open Tasker and create a task named 'Unlock' with the following items:
2) In Tasker, create a second task named 'Lock' with the following items:
3) In Tasker, create a third task named 'Check' with the following items:
4) Open AnyTAG NFC launcher and read your NFC ring - do not remove it from your phone's reading area yet! Configure the tag to launch the Tasker task 'Unlock'.
5) Once you've finished configuring the tag in AnyTAG, remove the ring from your phone. This should prompt you to configure the tag again. Configure this tag to launch the Tasker task 'Check'.
I'm not a Tasker expert. This solution is a bit shaky, but it works. There's definitely still room for improvement. If you've found a better way to do this, feel free to leave a comment.
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