It doesn't matter. According to the relevant public information, it is necessary to sign through the app on the mobile phone to prove that the master legal person service has been accepted by the customer. As long as the customer's after-sales service is through formal channels, there is no problem with signature confirmation. Mobile phones, called mobile phones or wireless phones, are usually called mobile phones. At first, they were just a communication tool. Early commonly known as mobile phones. They are portable telephone terminals that can be widely used. They were originally developed from 1940 battlefield mobile phones manufactured by Bell Laboratories.