Load different Unit content from Meta in API

functions.php

//video so app
add_filter('wplms_unit_metabox',function($box){
	$box[]=array( // Single checkbox
		'label'	=> __('Unit Content for App','vibe-customtypes'), // <label>
		'desc'	=> __('Unit Content for App.','vibe-customtypes'), // description
		'id'	=> 'vibe_app_content', // field id and name
		'type'	=> 'editor', // type of field
        'std'   => ''
    );
    return $box;
});

add_filter('vibe_wplms_api_unit_content',function($content,$post){
	$app_content = get_post_meta($post->ID,'vibe_app_content',true);
	if(strlen($app_content) > 2){
		return $app_content;
	}
	return $content;
},10,2);