You delete metadata from your images
Your smartphone invisibly attaches metadata such as coordinates, camera type, resolution, smartphone model or operating system to your pictures. With some camera apps, this can be partially or completely deactivated.
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If your phone is stolen, this data can provide information about your origin. Use apps like "Imagepipe" to clean up your pictures before you upload them to the Internet. You can install Imagepipe on your Android smartphone via F-Droid.