How to make your phone's data theft-proof

I recently witnessed a phone snatching in London. It’s not the first time, but this time I was able to help the victim, who was very concerned that his phone was unlocked when it was taken.

This incident got me thinking about the security precautions we should take to protect our data against in case of a phone theft.

So I’ve put together a compact, shareable guide to give you total peace of mind in the event that your phone is stolen, knowing that thieves won’t be able to get any valuable data out of it.

Below are all the steps you can take. Some of them do trade off convenience for added security, so I’ve listed them in order of convenience:

1. Configure screen lock after 30 seconds. This gives thieves less time to think about keeping the phone unlocked.

2. Erase data after failed passcode attempts. To prevent brute-force guessing of your passcode, you can configure your phone to erase all data after too many incorrect attempts.

3. Lock your phone when it goes offline. Often thieves might want to turn airplane mode on to avoid the phone being tracked. If they do, the phone will be locked. Android has this as a setting under “Theft protection”. For iPhone, you have to configure an automation in the Shortcuts app to “When airplane mode is turned on” → “Lock screen”.

4. Disable notification previews. Even if your phone is locked, criminals could see password reset codes, SMS messages and more from your lock screen. You can disable previews when locked for sensitive apps like Mail and Messages.

5. Require biometrics for specific apps. If your phone does remain unlocked, you can lock specific apps. Some sensitive apps, like Banking and Password Managers, already do this by default, but on iOS 18 you can now “Require Face ID” for almost any app. I suggest enabling this at least for these apps:

   • Mail: you receive reset codes here, and it stores a lot of sensitive info.
   • Text messages: reset codes also get sent here.
   • Two-factor authentication app: all your login codes are here!

Stay safe!