Crossing a border with your phone

A border is the one place where somebody can ask to look through your phone, has the authority to insist, and will hand it back afterwards. That combination makes it unlike every other privacy situation, and most advice written for phone theft simply does not apply.

Here is what actually changes the outcome, roughly in order of how much difference it makes.

1. Do not carry the data

This is first because nothing else comes close.

A document that is not on the device cannot be found, cannot be demanded, and cannot be argued about. Before you travel, sign out of and remove what you do not want examined, and restore it afterwards. For most people that is a twenty minute job each way.

If you travel often and the material is sensitive, the stronger version is a separate travel device that has never held any of it. This is what journalists and lawyers who cross borders regularly tend to end up doing, not because they are paranoid but because it is the only approach that does not depend on anybody's judgement at the moment of inspection.

2. Power the phone completely off

Not locked. Off.

An iPhone that has been powered on and unlocked at least once is in a state where a large amount of its data has already been decrypted into memory for the system to use. An iPhone that has been powered off and not yet unlocked is in a much stronger state: the keys for most content do not exist in memory, biometrics are disabled, and only the passcode can start the process.

The practical difference is substantial. Extraction tools are dramatically less effective against a device in that state, and some are not effective at all.

This costs nothing. Turn the phone off before you reach the checkpoint, not after somebody asks for it.

3. Understand what hiding does and does not do

This is where a lot of advice goes wrong, including advice about apps like ours.

Hiding content on the device works against a person looking through the phone. That is the common case by a wide margin: an officer scrolls photos and messages for a few minutes and hands it back.

Hiding does not work against forensic extraction. Software built for this does not browse your Home Screen. A hidden album is invisible to a human and irrelevant to a machine.

So hiding is worth doing, and it is worth being clear-eyed that it addresses the likely case rather than the worst case.

4. Know the rules where you are going

The legal position varies enormously, and in ways that matter.

In the United States, Customs and Border Protection has long asserted the authority to conduct a basic search of a device without suspicion. The consequences of declining differ sharply by status: a citizen cannot be denied entry for refusing, though the device can be seized; a visitor can simply be refused admission.

Other countries differ again. Some compel passcode disclosure with criminal penalties attached. Some do not ask at all in practice.

Two things are worth knowing in advance: what the rules are where you are going, and what your own status there means for refusing. This page is not legal advice and cannot be, but travelling without knowing either of those is a choice rather than an accident.

5. Decide your passcode answer before you are asked

If you are going to hand over a passcode, know in advance what it opens.

This is the part people improvise, and improvising goes badly. The decision is made in a few seconds, in a stressful setting, usually by someone who is tired. It is a much better decision made months earlier at a kitchen table.

Two traps:

An obviously scrubbed phone is itself a finding. A device with no messages, no photos, and three apps looks exactly like a device that was prepared for inspection. Ordinary clutter is protective.

A prepared space has to look lived in. If you are using an app that holds separate contents behind separate passcodes, the one you intend to hand over needs real material in it. We wrote about why in when somebody demands your passcode.

A short checklist

What we are not going to tell you

We are not going to tell you that an app solves this. Vessum is built for somebody holding your phone and asking for a passcode, which is a real and common situation and not this one at its worst. Against a device taken away for examination by people with the right equipment, the only thing that reliably helps is the first item on this page.

Anyone selling you a border-proof app is selling you something that does not exist. The unglamorous answer, which is to travel with less on the phone, remains the one that works.