coop0030 (263345) writes "Becky Stern at Adafruit has created a guide on how to create an open source NFC ring or other wearable to mod and unlock your Android phone. From the tutorial: 'Unlock your phone by just picking it up! No more pesky password or gesture PIN, just scan an NFC tag! This guide covers creating an NFC ring, putting an NFC tag in your nail polish, modding your Android installation to read tags from the lockscreen, and creating an automation toolchain to unlock the phone when the desired tag is scanned.' There is also a video that demonstrates how it works."