If you were to create a mobile app and wanted to create it on an operating system that would allow the users to personalize preferences within the operating system, you would use the

a0 operating system.

Android system

Explanation:

We could create a mobile app and allow some settings, in this case, the user can personalize preference like notifications, color, volume, sounds, passwords. This depends on the kind of app.

For example:

There is some bank application that you can use a password or you can use your digital print, or in some apps where you can change the color, for example black, in this way, you can care your eyes.