PRL, or Preferred Roaming List, basically tells your phone which towers to connect to first. Changing PRLs can improve reception and data speeds, and in some cases even give you access to corporate/test towers.
Because PRLs only operate on CDMA networks, this method only applies to Sprint and Verizon (ATT and T-mobile utilize GSM networks).
How to Change PRLs on the GS3 (Sprint Users ONLY)
Luckily for Sprint users, the method to change your PRL is very easy. All you need is a PRL file (a list at the end of this article explains them all).
Download the PRL zip you want to use and extract... more