Many current digital (2G & 3G) phones also feature the ability to roam on older analog (1G) networks. Analog networks typically have greater coverage than digital networks. Therefore, phones with analog roaming can use analog networks in many rural areas where digital service is not available.
Analog roaming, while useful in urgent situations, has several drawbacks compared to digital service: it is often more expensive, emits more radiation, sound quality is far less than digital, and certain features, such as caller-ID and data services, do not work with analog.