Hardware level encryption has long been supported by iOS, and all new versions seem to offer support to more features. Your storage in encrypted by default by Android ever since version 5.0 Marshmallow. They encrypt your data in both cases and can only be unlocked by the hardware in your phone.
Nonetheless, it is barely as tough as your key. Setting up a more complex code is one of the best security gadgets you can own.
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Other Ways to Secure your Smartphone: