@simonlg I could see now that the setting is not there, theme automatically detects for mobile and put the logic there in the template.
For this, you have to create a child theme and override content.php in it.
http://codex.wordpress.org/Child_Themes
Look at Line#61 in content.php, change the_excerpt() to the_content()
http://themes.trac.wordpress.org/browser/kippis/1.15/content.php#L61