How to send short messages to everyone?

Take Android mobile phone as an example: to send short messages in groups, you can click "+"in the recipient column to add contacts that need to be sent in groups. Tips: 1. A single Unicom user can send no more than 200 short messages in an hour at any time, and no more than 500 short messages during holidays (holidays refer to big holidays such as Spring Festival, New Year's Day and National Day). 2. The maximum number of messages sent by a single Unicom user in a single day shall not exceed 1000, and the number of holidays shall not exceed 2000 (holidays refer to big holidays such as Spring Festival, New Year's Day and National Day).