In Moodle, You can select different themes for different type of devices e.g. for desktops, for mobiles, for tablets etc.
You need to extract both folders in /theme directory of your moodle installation directory.
The moodletheme is to be used for the desktops only, and the moodlethememobile is to be used for moblie devices.
Note:- Here moodletheme means your downloaded theme.
You need to clear the theme cache after selecting a new theme everytime.