把以前美国ATT的sim卡装在iPhone 6后,会收到一短信:Your new device requires a new SIM card to give you access to all services。据说是因为Apple Pay需要NFC SE (Near Field Communication Secure Element) SIM卡。也有说是VoLTE需要。还有的说是因为新sim卡可以用新的频段,可以有更多LTE网络。