YSK: How to document that you are a US citizen
https://www.usa.gov/prove-us-citizenship
The most common way to show that you are a US citizen is to show a passport. However, only about 50% of US citizens have a passport.
An alternative to a passport is a Certificate of Citizenship.
Certificates of Citizenship and Naturalization show proof that someone is a U.S. citizen. The website https://www.usa.gov/prove-us-citizenship shows how you can get or replace these documents.
Prove your citizenship: born in the U.S. with no birth certificate. If you were born in the U.S. and have no birth certificate, learn how to get documentation to prove you are a U.S. citizen.
Prove your citizenship: born outside the U.S. to a U.S. citizen parent. Prove your U.S. citizenship without a birth certificate if you were born outside the U.S. to a U.S. citizen.
I’m sure as shit never unlocking my phone if asked, but I’ll show ID if requested in official capacity. If an unmarked person asks, I’ll tell them exactly where they can shove their request.