The more of these you implement, the safer your device will be.:
Use a Lock Screen and Enable Auto-Lock Functionality
Ensure your device requires a passcode, fingerprint, or similar factor to “unlock” it prior to use.
Ensure the device automatically enters the lock state when idle.
Do Not Leave Your Phone/Tablet Unattended
Treat these devices as you would treat cash.
Install Security Updates & Update Apps Regularly
Most importantly, ensure security updates are installed for the phone as they become available.
In addition to regularly installing security updates, ensure that all installed apps are regularly updated as well.
Be Careful When Opening Attachments and Browsing
Do not open unknown attachments or follow unknown links as these might infect your device with a virus.
Avoid Installing Unrecognized Apps or Apps From Unknown Authors
Always evaluate the legitimacy of apps prior to installing them on mobile devices. This includes making sure the software comes from a reputable vendor and is being downloaded from an official app repository.
Install Anti-Malware Software if Available
Just like computers, phones and tablets are also susceptible to worms and viruses.
If a Mobile Device Supports Encryption, Use It.
Some phones and tablets support encryption of the contents stored on the device. When possible, use this functionality. If your device is lost or stolen, encryption will help to prevent unauthorized access to your data.
This applies to external hard disk drives too.
Enable “Remote Wipe” Functionality Where Available
If the mobile device supports remote wipe functionality, use it. This allows for the data on the device to be remotely erased if the device becomes lost or stolen.
Enable “Find My Device” Functionality if Available
In case your device gets lost or stolen, you might be able to get it back with this service.
Be Mindful When Connecting to Unrecognized or Unsecured Wireless Networks
Be wary when connecting to unencrypted wireless networks (sometimes called “open” networks), since these types of wireless networks are particularly prone to eavesdropping.
Do not auto-connect to networks.
Turn off Wi-Fi and Bluetooth when you are not using them
Storing sensitive Information On Mobile Devices
Best practice - Don't store sensitive info on mobile device (e.g., credit card numbers, SSNs, passwords, etc.)
Even if device contents are encrypted, avoid storing sensitive or identifying information on mobile devices.
Do Not “Root” or “Jailbreak” Your Device
Rooting or jail-breaking your device could disable built in security features of your phone, like the firewall, and could install malware on your computer.
This can make it difficult to regularly pull down security updates and other patches for the device.
Ensure that your device is configured to automatically install updates as they become available.
INSIGHT: Smartphones and tablets have become such an integral part of our life, it's hard to imagine how people used to communicate, access and share information, and even pay bills without them. Because of their size, we tend to forget they are actually extremely powerful computers and they should be secured as such. The following security tips will help you secure your device and prevent malicious programs or people from accessing it.