There is a way to use a computer to send text messages to mobile phone users. Is this illegal?

Illegal. According to the "Interpretations of the Supreme People's Court and the Supreme People's Procuratorate on Several Issues Concerning the Specific Application of Laws in Criminal Cases concerning the Use of the Internet, Mobile Communication Terminals, and Audio Stations to Produce, Copy, Publish, Sell, and Disseminate Obscene Electronic Information", the Article came into effect on September 6, 2004. Article 1: Anyone who uses the Internet or mobile communication terminals to produce, copy, publish, sell, or disseminate obscene electronic information for the purpose of making profits and falls under any of the following circumstances shall, in accordance with the provisions of Paragraph 1 of Article 363 of the Criminal Law, be punished for producing , copy, publish, sell, and disseminate obscene materials for profit are convicted and punished. (3) Producing, copying, publishing, selling, and disseminating more than 200 obscene electronic publications, pictures, articles, short messages, etc.;