Trac Fone companies seem to prefer selling T-Mobile homed phones, followed by Verizon with AT&T as a last resort.
The database consists of an Acquisition table, which lists which radio frequencies to search for in which areas, and a System table, which tells the phone which towers it is allowed to connect to, and the preferred order.
The phone may change towers that the signal is drawn from, and the phone may begin to go into a roaming mode when it is too far from the home tower.
Roaming can cost the user more money, but a phone that has not switched to a roaming mode may not be functioning properly.
Once it has been updated for optimal service, a phone will work to its best capabilities.
Trac Fone and its sister brands NET10, and Straight Talk, do not have their own networks.