Customers often consult with device proposals, asking whether they are suitable for using IoT SIM cards. Through years of observation, I have found that monitoring devices with certain characteristics are particularly well-suited for this type of connectivity. They may not possess all five characteristics, but as long as they meet two or three of them, the advantages of IoT SIM cards can be significantly realized. Devices that require mobility rank first. This does not mean that the devices must literally run away, but rather that they may be installed in different locations or move with their carriers. Traditional network cables tether devices to fixed positions like a rope. IoT SIM cards free devices from this constraint; wherever they go, as long as there is cellular network coverage, data can be transmitted back. Devices with a wide distribution range are also very suitable. Some monitoring systems need to cover large areas, with devices spaced tens or even hundreds of kilometers apart. It is unrealistic to pull dedicated lines to each point, and the maintenance costs can be frighteningly high. IoT SIM cards use data billing, solving the connectivity issue for one point with a single card. Dispersed yet unified, this is precisely where IoT SIM cards excel. Devices deployed in remote areas often have no other choice. Weather stations in deep mountains, hydrological monitoring points in the wild, buoys at sea… these places lack existing network infrastructure. IoT SIM cards rely on mobile communication networks; as long as there is a signal, they can connect to the network. This enables real-time monitoring in areas that were previously unreachable. Devices with high real-time requirements can achieve significant improvements. Some monitoring data loses its value if it arrives an hour late, and some devices need to issue immediate alerts. IoT SIM cards maintain long-term online connectivity, allowing data to be transmitted as it is generated without manual intervention. This immediacy transforms monitoring from recording history to controlling the present. Devices that need to operate continuously for long periods are also suitable. Some monitoring tasks must last for several years or even longer without interruption. IoT SIM cards are designed specifically for device connectivity and will not deactivate due to silence like mobile phone cards. A stable connection ensures data continuity, which is the lifeline for many monitoring projects. These characteristics serve as five signposts, guiding devices to choose a more suitable connectivity method. Mobility, dispersion, remote deployment, real-time requirements, and long-term operation—each characteristic met increases the value of IoT SIM cards. Of course, it does not mean that devices with these characteristics must use IoT SIM cards. However, if you are selecting a connectivity solution for monitoring devices, it is worth comparing. A suitable solution can enhance device performance and generate greater value from data. IoT SIM cards are not a panacea, but they do provide a better choice for monitoring devices in specific scenarios. When devices need to be mobile, widely distributed, located in remote areas, require real-time operation, or need to run for long periods, the value of this connectivity method becomes evident. The significance of technology lies in solving problems. For monitoring devices with these characteristics, IoT SIM cards may be the most suitable solution. They make monitoring more flexible, widespread, and timely, and also enhance the value of data.