If you do not know, for over a year, the Supreme Court issued a judgment entitling police to conduct a search of an inmate’s cell if the latter is incidental to the arrest and the officer reported his search in his notes accurately.
Almost a year later (November 2015), it is the Supreme Court of the United States who received a request from a defendant who claimed to have been injured in his rights when the police asked his cell phone provider, his location at specific times. He asked the court to rule that his right to privacy had been bullied.
The information on his location have established that it was on the premises at many crimes for which he received a sentence of 162 years in prison. The court simply rejected to rule on the merits that the police have a warrant or not, leaving the police a path to do their job.
With the resurgence of acts of terrorism, indoctrination via social network to radicalization and also the many crimes committed with cell (filming an attack, for example), it is comforting that the police is free to run properly their investigations to protect society.
Certainly all this technology is a real headache for lawyers and defenders of privacy but when a search is on the offense or used to provide physical evidence in an investigation, it must serve society and not criminals.
Cellular service providers are receiving more and more requests from various actors of justice. They can transmit the precise location, sent and received text messages, identify incoming / outgoing calls. All this to help solving crimes.
Maybe this will only tell criminals to perpetrate their crimes without their favorite mobile device but in any case you are stopped while driving a cell phone in your hands or another crime, know that the police have the right to search your mobile device, for a more secure society!