1) Set up a PIN in a SIM card
The PIN number is a password that permits access to calls and mobile data use.

You can set up a PIN using between four and eight digits (the latter is recommended), but make sure to use one that avoids a string of numbers that is easy to decipher. Sequences such as 1234, 1111, 1122, etc., should be avoided.

2) Set up an access code
In order to avoid unauthorized use of devices and, therefore, access to personal information, you should establish an access code for the lock screen.

According to the model of the device you have, there are different blocking mechanisms: pin, patterns, biometric screening and password (a combination of alphanumeric characters).

We recommend you configure your device so that automatic blocking of it is activated after a short period of inactivity, in order to avoid unauthorized access to personal data in the case of theft or loss.

3) Download applications from official sites
There are platforms and websites that could be infected with malware that allow the downloading of applications. To minimize the risk of infection, it is advisable not to install apps from unknown sources in mobile devices rather than official sites: Google Play in the case of Android and App Store for iOS.

4) Exercise care with application licenses
Many applications installed in mobile devices require permissions to work. You should check out the nature of licenses they ask for and exercise common sense to decide whether what is requested is reasonable in terms of the use of the application.

If more is asked for in the license than is necessary to allow installation, it is best not to proceed. It is likely there is an alternative that only asks for what is essential.

Smartphones allow you to manage permissions and it is recommendable to disable those that are unnecessary and to review them on a regular basis.

5) Enable location and connection features only when needed
It is advisable to disable location and bluetooth features when they are not required, in order to protect your privacy.

Likewise, you should review location and privacy settings in social networks and to maintain disabled options that allow automatic location in all applications installed in smartphones.

6) Clear WiFi history on a regular basis
In order to avoid unintended connection to untrusted wireless networks, it is advisable to clear the connection history of those that are not used regularly and to review them on a regular basis.

Likewise, care should be exercised in connecting to public networks, to avoid sending personal data and sensitive information.

7) Use an antivirus program
If the mobile device uses the Android operating system, you should install an antivirus program to enhance security. You can find free antivirus programs on the OSI website.

The risk of viruses for iOS users is lower because the system does not allow downloads other than from the App Store, provided jailbreak has not been used. Likewise, it is not advisable to root devices with the Android operating system.

8) Respond to operating system update notices
Updates of operating systems usually correct security problems. It is important to attend to notices of system updates.

Similarly, in order not to leave yourself exposed to known weaknesses exploited by hackers, applications need to be in the latest update.

9) Make back-up copies
Back-up copies safeguard against the loss of information in the case of the loss or theft of a device.

When changing a mobile device, it is recommended that you should clear all personal information stored in the smartphone being replaced, particularly if it is sold or gifted to a third party, in order to protect personal data as well as privacy.