By default, the app uses Ionicons. If they don’t have an icon you like, you can use Font Awesome icons.
You can add  Font Awesome icons to your menus by adding fa-{icon_name} to the menu’s icon class field.  For example, if you want use the car icon from Font Awesome add fa-car to the icon class field.
Note: you can use these fonts in your tab (footer) menu; however, they don’t have outlined icons like the Ionic icons. Â iOS uses the outline icons for the unselected tab items.

Font Awesome in Custom Pages
You can use Font Awesome in custom pages by adding the fa and fa-icon classes to your HTML element. Â The custom pages require both the fa and fa-{icon} classes, but to use it in the menu you only need to use the fa-{icon}.
<span class="fa fa-car"></span>