What is business communication?

BusinessCom is a PDA (in a sense, it is not real) produced by Henderson Ye Wei Company. It has a simple information management function and can store a variety of information such as telephone numbers and addresses. Most of them are monochrome screens, with limited resolution and weak entertainment functions. Compared with the current PDA, they have almost no extended functions. Many years ago (I can't remember how many years), the mobile pager business was indispensable. Nowadays, many mobile phones (non-intelligent) have far more functions than Shanglian, so now Shanglian has withdrawn from the market. Henderson Ye Wei recently launched a stealth mobile phone, which is said to be very good, but personally it feels terrible! Hey hey, I hope you can be satisfied with my explanation!