[SOLVED] Is telephony manager values reliable and changeable (cdma)?

Is telephony manager values reliable and changeable (cdma)?

I want to know if I can rely on the telephony values like country, MCC, etc on Android for my app. Can I change them on the run using setprop? I tried changing using setprop it didn't seem to work. From my understanding telephony manager is a class/interface which represents Hardware configuration of GSM or CDMA. In case of GSM this could be sim and in case of CDMA it cud be a hardware. My questions are:

Who update these values in both the cases for the first time?
Are these values are saved by OS as read only?
What if a user travels to different country or zone will some of the values like country code and MCC values updated automatically?
Can I reset these values?

I have no intention of changing any of these values but want to understand its working! I would appreciate if someone can help me on this.

Solution

@Bo The way CDMA works is different from GSM. CDMA has always got one home base and many visitor base location. and you can always get to know about visitor Operator using TelephonyManager methods which is considered as unreliable for CDMA.