“…Ghadirian et al (2018) also focused on SA's application in higher education, and presented a more comprehensive review by including both journal articles and conference papers, yielding 71 reviewed papers. Krouska et al (2018) review focused on the comparative analysis of 15 SA technologies, such as Diigo and HyLighter, pinpointing their advantages and limitations, and concluded that personalized annotations and video annotations technology should be further developed. With teachers as their target audience, Zhu et al (2020) located 39 related articles for their review, especially as a timely response to the online teaching and learning challenges which have emerged during the pandemic, and proposed five categorical benefits of SA, including enhanced literacy skills, more efficient instructor and peer assessment, more structured argumentation and inquiry, deeper domain‐specific understanding, as well as improved transactional distance; however, they did not identify such information as research trends, issues or frontiers that point out directions for future researchers.…”