Iphone4s, without sim card, can receive SMS?

The information received is not SMS, but iMessage, which is a way for Apple to use cellular data traffic to transmit SMS. It doesn't need to pay the SMS fee, but it needs to pay the cellular data fee. After you connect to WIFI, you can send messages without spending, which is very convenient and fast. Moreover, in the short message system, the blue message is iMessage, and the green message is a short message sent by a normal mobile phone. You have not installed the sim card. Therefore, all your SMS services are imessage, and you can also use Facetime to make video calls with iPhone friends through wireless networks, without spending cellular mobile data traffic, and you can also socialize through Apple ID.