Is the SMS port hidden or helpful?

Neither. Short message interface is a short message service provided by mobile operators, which allows users to send and receive information through short messages without using e-mail or other Internet connections. Concealment refers to hiding or covering up certain behaviors or facts in order to avoid being discovered or punished. Help letter refers to helping others to commit criminal activities, such as money laundering, fraud or theft, so the short message port is not a hidden or help letter.