Encryption is only effective when the phone is switched off. Therefore, practise how to switch off your phone quickly in stressful situations.
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Even if your phone is encrypted, software such as Cellebrite can access it via USB. As long as your phone is switched on, encryption is ineffective. Encryption is only really effective when it is switched off. Be sure to switch off your phone before you give it into someone else's hands! If you want to be on the safe side, you can also attach a killswitch to your phone. This allows you to quickly remove the battery in dangerous situations. The key will then disappear from your device's memory.