Protect your phone and others at a protest

1. Your usual phone: easiest, but everything on it goes with you. Prepare it with the next items.
2. A second phone: an old or cheap phone with little personal data on it, as long as it still gets security updates. Don't sign in to your personal email or social media on it. Write your friends' numbers down on paper too.
3. No phone, or a phone that stays off until you need it: the strongest option for your data, and the weakest for staying in touch.

A second phone leaves its own trail. In most countries a SIM card is registered to an ID, and mobile masts record where a phone has been. If you carry both phones, their locations can be matched. Switch the second phone off before you go home.

1. Install the latest updates for the system and your apps.
2. Back up the phone and keep the backup somewhere safe: see Turn on your phone's backup.
3. Delete what you don't need to carry. Check the photo and video folders in your messaging apps, and empty the Recently Deleted or trash folders: deleted items often wait there.
4. Sign out of apps you won't need, especially ones holding a lot about you or your family. Sign in through a browser if you need something, and sign out after.
5. Hide message previews on the lock screen: see Hide message previews on the lock screen.
6. Write an emergency contact and a lawyer's number on paper, and keep it on you.
7. Check your emergency information on the lock screen. If your iPhone's Medical ID is set to Show When Locked, or your Android phone shows emergency contacts when locked, anyone holding the phone can see them. List only a lawyer, or turn this off. On iPhone, the same contacts get a text with your location after an emergency call.
8. Charge the phone, take a power bank, and download an offline map of the area.
9. Consider Lockdown Mode on iPhone or Advanced Protection on Android.

Deleted content can sometimes be recovered with specialist tools. A memory card in the phone, or a separate camera, is usually not encrypted.

1. Open the camera from the lock screen, so that the phone stays locked if it is snatched. On iPhone, swipe left on the lock screen. On a Pixel, double-press the power button (Settings → System → Gestures → Double press power button). On Samsung, double-press the side button (Settings → Advanced features → Side button).
2. Before posting, cover faces, tattoos and distinctive clothing with solid blocks: use the image redaction tool. EFF says blurring can sometimes be reversed.
3. Remove the location and other hidden details from the file: use the photo metadata tool or see Remove location from your photos.
4. Check the background too: reflections, street signs and other people.

If you are documenting events, the hidden details can help prove when and where a photo was taken: keep the original safe and post a cleaned copy. Face detection in apps misses faces, so check every photo yourself.

1. Switch the phone off completely, not just to sleep. Freedom of the Press Foundation explains that a phone that hasn't been unlocked since it was switched on is harder for forensic tools to break into.
2. On iPhone: press and hold the side button and either volume button until the sliders appear, then drag the power-off slider. Don't keep holding past the sliders.
3. If you must make a call, switch the phone on, call, then switch it off again without unlocking more than you need.
4. Don't wipe the phone remotely or use a wipe code without talking to a lawyer first. CPJ notes that wiping can make you look more suspicious, and a remote wipe works only if the phone is online.

Switching off doesn't help if the phone was taken while unlocked. Freedom of the Press Foundation reports that an iPhone restarts itself after 72 hours locked, and that one forensic vendor claims its tools can get past this. Don't rely on it: switch the phone off yourself.