LTE-M and NB-IoT (cellular IoT)

LTE-M and NB-IoT are pared-down forms of 4G LTE designed for small, infrequent messages and long battery life. LTE-M supports higher data rates and mobility; NB-IoT uses a narrower channel for very low data rates and better coverage deep inside buildings. Both support power-saving features such as Power Saving Mode (PSM) and extended discontinuous reception (eDRX), which let a device sleep for long periods while staying registered on the network.

Cellular IoT makes a product independent of the customer's Wi-Fi, which is valuable for meters, trackers, remote equipment and anything installed outdoors or in commercial sites.

Where it bites: availability of each technology varies by country and carrier; devices typically need carrier certification on top of FCC/CE approval; SIM or eSIM provisioning and data plans become a recurring cost; and network sunsets can strand hardware in the field.