So, this transforms into some sort of "spring loaded Home button that double's as a Touch ID ?"
First flaw of its spring loaded, users will break it... more. (u can almost count on it)
This would be a givin, and take the pressure of all those nay-sayers that say using touch controls are too hard... when playing Prince of Persia...
(As usual, they'd have to be right

)
Next thing you'll know Apple will say this is "so popular" and bring it to iPad, at which time i'll cry.. You just know that anything successful, Apple will make it across all other devices..... Why would they not ? Its their game to do that.