It seems to me that one possible solution is to back up your phone onto an micro-SD card (possibly one other than the one you usually have installed), using an app to do this, and wiping most of the phone except for some functions..  (I'm assuming this is already available, or could be written if this is big issue for many people.)    Micro-SD cards of 128 Gigabytes capacity are now about $20, and they are so small that they could easily fit behind most postage stamps, on envelopes.   Those about as old as me (61), or older, probably remember when "micro-dots" were a big plot element in spy novels, probably the 1950s and 1960s.  https://en.wikipedia.org/wiki/Microdot   Then, it was considered remarkable that a page of text could be photo-reduced in this way, possibly being stuck behind a postage stamp.   A 128 gigabyte micro-SD card can hold the equivalent of about 16,000 Encyclopedia-Britannica-sized volumes.  (Which, of course, dates me too:  Many kids today have probably never seen a paper encyclopedia...) A week ago, I got to the end of watching the TV series, "The Americans" about a Russian couple who act as spies in Washington D.C. for 25+ years.  Inspired by a 2010 case from Seattle, I believe.   My main objection to the plot of the series is that they repeatedly had to kill people merely to ensure their continued anonymity.  My understanding is that there are drugs which can erase a person's day's waking memory.   https://en.wikipedia.org/wiki/Blackout_(drug-related_amnesia)This would allow them to interrogate someone else, and then deliberately cause him to forget the recent incident.  No need to kill anyone.                   Jim Bell https://www.npr.org/2019/05/02/719337356/aclu-border-agents-violate-constitu... [partial quote follows] The American Civil Liberties Union says it has uncovered new evidence that federal border agents are violating the Constitution when they search travelers' electronic devices. The ACLU, along with the Electronic Frontier Foundation, sued the federal government in 2017, alleging that its "warrantless and suspicionless searches" of electronic devices at the U.S. ports of entry violated the First and Fourth amendments. Lawyers now say that, through depositions of border agents, they have learned that the scope of the warrantless searches has expanded far beyond the mere enforcement of immigration and customs laws. Border officers have the authority to search belongings for contraband, or to determine who is admissible into the U.S., the ACLU said. But agents now "claim authority to search travelers' devices for general law enforcement purposes, such as looking for potential evidence of illegal activity beyond violations of immigration and customs laws," plaintiffs wrote. "That claimed authority extends to enforcing 'hundreds' of federal laws, including tax, bankruptcy, environmental, and consumer protection laws. Defendants' asserted purposes for conducting warrantless or suspicionless device searches also include intelligence gathering or advancing pre-existing investigations." These practices violate the Fourth Amendment's protection against unreasonable search and seizure, the ACLU wrote. They also violate the First Amendment, attorneys said, because people traveling to the U.S. might censor themselves, knowing that a border agent might look through their phone.[end of partial quote]