Many people in life will ridicule:? Every day, the distance that fingers slide on the mobile phone screen is longer than the distance that they walk! ? With the browsing at the fingertips integrated into all aspects of life, how to make the user's fingers slide more efficiently and see more things he wants to see while sliding his fingers, instead of sliding his fingers in vain, is an important aspect to improve the user experience of mobile APP. In order to deeply understand people's APP browsing behavior, we use an eye tracker specially used to track the mobile device's gaze behavior to study the user's habit of browsing social APPs, trying to show the characteristics of people's APP browsing more intuitively, and the resulting thinking on optimizing the design of app browsing experience. What's the difference between mobile phone and PC browsing? We have conducted eye movement tests for the PC version of QQ space and the mobile version of QQ space, allowing users to log in their QQ space and browse their friends freely. Comparing the results of the two tests (as shown below), we can find that users slide their fingers more frequently when browsing their friends on their mobile phones, and often browse the content while sliding their fingers. When analyzing eye movement data based on computer web pages, we mainly pay attention to the user's gaze focus and trajectory, but for mobile phones, it is not enough to only analyze what users look at and what they don't look at. It is necessary to give consideration to both eye gaze and finger sliding to analyze the user's browsing characteristics and evaluate the user's browsing efficiency. During the eye movement test of the mobile version of QQ Space, we found that sometimes users are obviously interested in a certain trend, but they just slide the screen and don't look at the content until the content is adjusted to a certain range. This situation obviously reduces the browsing efficiency of users and increases the sliding distance of fingers, but they don't see more content (as shown below). In this study, we call this scenario? Inefficient sliding? . The scene of inefficient sliding makes us wonder: since users don't browse the whole screen from top to bottom before sliding up the screen, how big is the user's gaze range? How to optimize the design based on the gaze range to reduce the inefficient sliding of users? Can the user's gaze range be changed? What is the gaze range on the fingertip? Taking the mobile version of QQ space as an example, we used Tobii X 120 eye tracker to test 24 users' eye movements, and let them log in their own QQ space to browse their friends' trends freely. The results show that the length of gaze range accounts for about 75% of the length of mobile phone screen (excluding top bar and bottom bar), and the length of Facebook gaze range accounts for 87% of the length of mobile phone screen (excluding top bar and bottom bar). In order to better analyze the formation of gaze range, we also study the gaze of users when browsing a single dynamic. Facebook's dynamic is card design, and the interval between two dynamics is obvious. When users browse a dynamic, they usually slide it to the top of the screen and start browsing. In addition, the total height of words and pictures is within one screen, so users can see the bottom edge of the picture in one screen, which enables users to browse the words and pictures directly and completely in one screen when browsing a dynamic they are interested in. It is rare that they start to slide the screen to adjust the position of the picture after reading the words, thus making the gaze range adjustable. From this, we infer that when using social APP, the user's gaze range is not fixed, and the user's gaze range can be expanded through design changes, which can not only make better use of the screen size, but also reduce the inefficient sliding of users and improve browsing efficiency. Of course, this is only an inference obtained by comparing the mobile version of QQ Space with the mobile version of Facebook. What design elements affect the gaze range and how the design changes affect the gaze range are issues worthy of further study. Summary: This paper mainly reveals the characteristics of users browsing social apps, and tries to bring some inspiration to the design of apps from the perspective of browsing experience. In view of the user's gaze range and inefficient sliding, how to expand the gaze range and reduce inefficient sliding through design changes is a problem worthy of consideration when designing dynamic presentation methods in social apps. At the same time, for other types of apps (such as information, etc.), what are the characteristics of users' gaze range? What are the similarities and differences with the gaze range of social apps? Can you sum up some criteria to improve the design of APP browsing experience by comparing the gaze range of different types of apps? For these questions, we will continue to carry out relevant research to find answers.