Are there easy ways to delete data—files, photos, etc.—on phones so it can’t be recovered? Does resetting a phone to factory defaults erase data, or is it still recoverable? That is, does the reset erase the old encryption key, or just sever the password that access that key? When the phone is rebooted, are deleted files still available?

We need answers for both iPhones and Android phones. And it’s not just the US; the world is going to become a more dangerous place to oppose state power...

CBP’s inspection of people’s phones, laptops, tablets and other electronic devices as they enter the country has long been a controversial practice that the agency has defended as a low-impact way to pursue possible security threats and determine an individual’s “intentions upon entry” into the U.S. But the revelation that thousands of agents have access to a searchable database without public oversight is a new development in what privacy advocates and some lawmakers warn could be an infringement of Americans’ Fourth Amendment rights against unreasonable searches and seizures...