Depending on your operator/locality, and whether you're okay with being limited to voice and barely a 100 kbit/s of data, it might "just work", no need to do anything special. Your 3G phone will happily fall back to 2G/2.75G (a.k.a. GSM/GPRS/EDGE), where such network is available.
For example, in the Netherlands, KPN, the last operator to switch off 3G, is planning to do so at the end of this month.
2G, on the other hand, is still in the air, with commitments to keep it alive until 2025, possibly longer.
For example, in the Netherlands, KPN, the last operator to switch off 3G, is planning to do so at the end of this month.
2G, on the other hand, is still in the air, with commitments to keep it alive until 2025, possibly longer.
Source (in Dutch): https://www.kpn.com/zakelijk/blog/de-toekomst-van-iot-vraagt...