These days, I found that the reception of SMS by iphone5 was delayed.

Information delay is not necessarily a problem with mobile phones;

The signal coverage in 1. area is poor, and the signal is weak or fluctuates periodically.

2. There is transmission delay between different operators. For example, China Unicom sends mobile, and telecommunications sends China Unicom and so on. This is a normal phenomenon.

3, or often put the mobile phone in a drawer or bag to artificially weaken the signal field.

Of course, there may be something wrong with the antenna of the mobile phone (which is not common in 4S). Find another 4S to compare the signal strength of the two and observe for about 5 minutes.

Finally, you can also call the operator to ask this question.