At Wired, Andy Greenberg and Lily Hay Newman lay out precautions to take with your tech when you’re protesting:
If you insist on using biometric unlocking methods to have faster access to your devices, keep in mind that some have an emergency function to disable these types of locks. Hold the wake button and one of the volume buttons simultaneously on an iPhone, for instance, and it will lock itself and require a passcode to unlock rather than FaceID or TouchID. Most devices also let you take photos or record video without unlocking them first, a good way to keep your phone locked as much as possible.
I’ve also seen several people online pointing out that if you want to share a photo of a protest, it may be better to take a screenshot of that photo—the rationale being that screenshots don’t contain location or other metadata. (In iOS, take a screenshot by pushing the Sleep/Wake button and the volume up button at the same time).