Shared here for public benefit.
Before going to a protest, demonstrators or observers should note that their cellphones may subject them to surveillance tactics by law enforcement. If your cellphone is on and unsecured, your location can be tracked and your unencrypted communications, such as SMS, may be intercepted. Additionally, police may retrieve your messages and the content of your phone if they take custody of your phone, or later by warrant or subpoena.
They may confiscate your phone and record all data on it.
If it’s a fresh wipe with a good passcode, and you keep it on airplane mode, you’re probably fine.
Set up a duress PIN on your graphene phone
Graphene is not a good OS for this type if work. Yes it’s secure, no good backup solutions. You will lose all your data upon confiscation. Graphene again is secure but if all your data is gone what good will it do? DO NOT TAKE YOUR PERSONAL DEVICES.