[jlund3]

Supposing all this is true, and you leave your phone/laptop at home, what stops the the border control agent from demanding that you log in to your email and social media accounts on a device they provide before allowing entry?

[phicoh]

Change the password to something you cannot recall. A long randomly generated password that you leave at home.

Works best if you are a citizen of the country you try to enter.

[justindocanto]

Two factor authentication.