The aim is to identify the impact of mobile viewing practices on narrative strategies and economics of the web series industry. The relevance of the work is due to the rapid growth of the vertical video market and its growing influence on the global media industry, while this format remains insufficiently studied in academic discourse in Russian. The research methodology includes an overview-analytical method, formal narrative and discursive analysis, as well as analysis of industrial data. Based on the study of more than 20 specific series and reports from analytical agencies, the specific features of the format are revealed. A detailed definition of vertical microseries is given as a modular audiovisual form optimized for mobile platforms. The key narrative features are revealed: plot-driven orientation rather than character development; the use of “hooks” and cliffhangers; compensation for the predictability of the plot due to visual entertainment. The ambivalent role of the format is revealed: on the one hand, thematic freedom and the use of the current Internet language, on the other – dependence on adaptations (IP) and the risk of creative homogeneity. The transformation of the industry’s business models towards algorithmic distribution and detailed monetization schemes integrated into the ecosystem of short videos is analyzed. It is concluded that the vertical microseries is a promising universal format, whose success is based on a unique combination of relevant media forms, interactive consumption practices and commercial efficiency, which provides it with the potential for deep integration into the global media space. © Си Л., Новикова А.А., Сун Ц., 2025.