Secure Your Mobile Device
To prevent thieves from gaining access to your personal information, make sure that your mobile device is protected.
Use a strong PIN (or passcode) with at least 6 digits.
Encrypt your files.
Set the screen lock on your device to activate immediately when it's not in use.
Make sure your OS version is supported by the vendor.
iOS
To set up a passcode, follow the instructions on the Apple Support site: Use a passcode with your iPhone, iPad, or iPod touch.
Once you've set a strong passcode, your device will be encrypted by default.
Android
Newer Android devices are encrypted by default once you pick a pattern, numbered PIN, or mixed password for your lock screen. To set up a passcode, follow the instructions in the Set screen lock on an Andriod device Google support article.