Regarding the monitoring software on a phone I would consider it a weapon that can be used against you involuntarily
Cell towers already do that to an extent but I guess the difference is that if your phone is stolen and the police aren't after you its not going to be traced with the alternative of everything is logged and traced back to you whether you want it to be so or not.
this is a very good argument as to why this feature should not be implemented. However I would think that the phones would be disabled via the cell towers regardless so if they have no connection to the towers then the phone company would have no way of disabling it (for example if the phone was kept in airplane mode)
Well if they are dedicated enough someone can still get the phone to send a transmission via forcing the tower to geolocate it even in Airplane mode.
7. Police Can Activate Phone GPS Location Tracking
Can police access the GPS data on your phone? According to a recent court ruling, they can not only access it, but activate GPS location tracking if it's disabled. That's one takeaway from last week's U.S. Court of Appeals for the Sixth Circuit ruling in a case involving Melvin Skinner, who was convicted of drug trafficking--and sentenced to 20 years in jail. Skinner argued that the GPS data tracking, which DEA agents used to track a motor home he was driving that was filled with 1,100 pounds of marijuana, violated his Fourth Amendment right against unreasonable search. In addition, according to a close reading of the court ruling, it turns out that police may not have merely tracked Skinner, but actually instructed his prepaid phone provider to activate the GPS functionality. The court, however, ruled that the DEA had acted lawfully.
http://www.darkreading.com/risk-management/7-facts-about-geolocation-privacy/d/d-id/1105877?http://www.informationweek.com/mobile/lose-the-burners-court-okays-prepaid-phone-tracking/d/d-id/1105814?Appeals court rules law enforcement agencies don't need a warrant to "ping" and track prepaid cellphone locations.
Prepaid cellphone users may be tracked by law enforcement agencies at any time, without police first having to obtain a probable-cause warrant.