This would be useful beyond getting in and out of customs too. For instance, most people don't want to carry around a work phone and a personal phone, so we end up mixing two personas on one device, and it gets awful. For instance I keep two 2fa apps, one for work stuff and one for personal stuff. It would be so much easier if I could have a separate login that showed just my work apps. Like ... wouldn't it be nice to only have to see work slacks when you log in using a work persona?
Recent enough Androids have this "Work Profile" feature. You get two app stores, and work apps get little "work" overlay. There are separate lock settings and sound/notification settings for work profiles too - I think this means you can have simple pincode for personal stuff and more complex for work one. And you can turn off all work apps at once with a single button press. And if your admin gives "remote wipe" command, only work apps are wiped.
Sadly this is automatic, which means regular people can't use it. You workspace admin got to enable MDM, and then phone will prompt you if you want a work profile when you try to install it.
Side note: The sibling comments talk about creating a work profile which is different in that it still lives within the same user account and is not fully isolated.
Android 15 has a "Private Space" feature that can be somewhat hidden and used to sandbox apps/data. It will prompt for a secondary unlock if you know where to look.
"Private" in marketing terms only. Border agents have access to it all. If you refuse to turn over all of your passcodes and passwords for the access they're after (including social media profiles), they can detain you and seize your device.
Border Patrol is a step above most law enforcement when it comes to authority. The Fourth Amendment doesn't apply in the 100 mile border zone, or at least SCOTUS ruled Congress hasn't defined what happens if it is violated by border patrol (Egbert v Boule).
