Recently, interest in gamification has been increasing. With the advent of the smartphone era, game design techniques are being used for smartphone applications, which have rapidly increased consumption, and their necessity and usefulness has become widely known. This paper introduce some definitions and category of gamification and suggest modified concept of gamification, Also this paper introduce representative examples in various fields. Lastly this paper identify the limitations of gamification through the analysis of various examples. Although we acknowledge the importance and effectiveness of gamification, it is more important to understand the advantages and limitation of it when we apply.