From Mika myrseth on 2017/08/10 00:17:33 +0000
Using wifi signal strength, measured in bed and for example bathroom. Makes you required to walk to the other location, but no need to scan like QR and NFC.
It’s implimented in an app called AMDroid.
Copied from original feature request: http://urbandroid.uservoice.com/forums/264867-sleep-as-android/suggestions/20479846-wifi-captcha