If the company clearly stipulates that mobile phones are not allowed in training, and the regulations are formulated through democratic procedures and publicized to workers, then it is legal and normal for the company not to bring mobile phones during training time. However, if the company forcibly accepts the mobile phone, it is illegal, and employees can call the police or go to court to ask for it back.

In addition, if it is required for safety in production or confidentiality, it is forbidden to use mobile phones in accordance with relevant state regulations. In short, employers are required not to bring their mobile phones during training, and must abide by relevant regulations and procedures, so as not to infringe upon the legitimate rights and interests of workers.