What does Holding Home Button on Power Off Screen do? When you hold the home button on the power off screen of an iDevice on the lockscreen or Springboard, what is it supposed to do?
If you continue to hold, you get Siri [iPhone 4S &amp; up]; even from the power-down screen…  

…otherwise, you trigger fingerprint security, which requires you to touch but not press the home button from the lock screen to unlock the device [iPhone 5S &amp; up].