$100/4 isn't going to be a burden for most apple customers if they're just putting them on their keys, wallets, handbags, etc. But the endgame for these sorts o

$100/4 isn't going to be a burden for most apple customers if they're just putting them on their keys, wallets, handbags, etc. But the endgame for these sorts of devices is longer lifetimes and slapping them on everything you might conceivable care about losing, which will only become practical once they hit prices below $1. Maybe something based on semi-passive RFID?