Recently, X-MOL, the famous chemical information platform, reported a review paper published on Advanced Functional Materials on its Wechat public platform. The review is entitled "Recent Advances in Pen-Based Writing Electronics and their Emerging Applications". In this review, state-of-art advances in techniques for direct writing of electronics are presented, and pros and cons of each fabrication route are discussed. Emerging applications of pen-based writing electronics are also summarized. Based on these, final conclusions, limitations and challenges, as well as ongoing perspectives are illustrated.