gbiggie
La patience et le pardon
Welcome to Android Forums king lionwhat is this for

This is the answer as quoted from the OP(original post)

he PRL helps determine which home-network towers to use, and also which towers belonging to other networks to use in roaming situations (areas where the home network has no coverage.) When roaming, the PRL may instruct the phone to use the network with the best roaming rate for the carrier, rather than the one with the strongest signal at the moment.
Since a PRL tells the phone "where" to search for a signal, as carrier networks change over time, an updated PRL may be required for a phone to "see" all of the coverage that it should, both with the home network and for roaming.



