code: protected function getMobile(UserEntity $user) 
  	{
  		$metadata = $user->getMetadata();
  		foreach($metadata as $meta) {
  			if('cellulare' == $meta->getKey()) {
  				return $meta->getValue();
  			}
  		}
  		
  		return null;
  	}
docs: Return mobile meta value
  
  @param UserEntity $user
  @return string|NULL