I gave the title perfect app for construction or destruction because if we want to construct our life in a good way then we learn many knowledgeable things by watching useful videos. In this way youtube act as constructor whereas many people destruct and waste their time by watching useless video on youtube. In this way youtube act as destructor. We can also earn lots of money by posting our ownmade videos through monetisation( monetisation is the process by which we can enable our video to earn money) . So I recommend to use this app in useful way.