What's the difference between caller ID and caller assistant?

Caller ID means that when you are called, you will display the other party's mobile phone number on your mobile phone. If you have stored the other party's number, it will display the other party's name and the monthly caller ID of 6 yuan. The caller assistant is what we call a caller reminder. Call alert means that when your mobile phone is out of service or turned off, you can't answer the phone normally. When you are in the signal coverage area or turn on the phone, the system will automatically send a short message to your mobile phone, including the time and number to call you. This service is 3 yuan every month! If you don't understand, please keep asking questions, and I will give you an in-depth answer! ! thank you