Police in The United States can’t search your cell phone without a warrant. That is the result of the United States Supreme Court decision in the case of Riley v California.
The SCOTUS ruling that police must obtain a search warrant to browse through a cell phone means that a cop can’t just look at anyone’s phone during even in the act of arresting them.
The police generally may not, without a warrant, search digital information on a cell phone seized from an individual who has been arrested.
It opens the door to the existence of a complete and related range of rights for video-bloggers, as well.
That because a person making a video of, say, an example of police brutality as it happens, can escape fear that an officer can 1) stop that person from making the video, because of such an action is occurring on the street that’s the public domain, and the video-blogger has free speech rights to make a video, and 2) the officer can’t look at the contents of the cell phone right then because of the Supreme Court ruling.