Prior studies on mobile app analysis often analyze apps across different categories or focus on a small set of apps within a category. These studies either provide general insights for an entire app store which consists of millions of apps, or provide specific insights for a small set of apps. However, a single app category can often contain tens of thousands to hundreds of thousands of apps. For example, according to AppBrain, there are 46,625 apps in the "Sports" category of Google Play apps. Analyzing such a targeted category of apps can provide more specific insights than analyzing apps across categories while still benefiting many app developers interested in the category. This work aims to study a large number of apps from a single category (i.e., the sports category). We performed an empirical study on over two thousand sports apps in the Google Play Store. We study the characteristics of these apps (e.g., their targeted sports types and main functionalities) through manual analysis, the topics in the user review through topic modeling, as well as the aspects that contribute to the negative opinions of users through analysis of user ratings and sentiment. It is concluded that analyzing a targeted category of apps (e.g., sports apps) can provide more specific insights than analyzing apps across different categories while still being relevant for a large number (e.g., tens of thousands) of apps. Besides, as a rapid-growing and competitive market, sports apps provide rich opportunities for future research, for example, to study the integration of data science or machine learning techniques in software applications or to study the factors that influence the competitiveness of the apps.

翻译：现有关于移动应用分析的研究通常跨类别分析应用，或聚焦于某类别中的少量应用。这些研究要么针对包含数百万应用的整个应用商店提供宏观洞察，要么针对少量应用提供具体见解。然而，单一应用类别通常包含数万至数十万个应用。例如，根据AppBrain统计，谷歌应用商店"体育"类别中包含46,625个应用。与跨类别分析相比，针对特定类别应用进行分析能提供更具体的见解，同时惠及对该类别感兴趣的众多开发者。本研究旨在探究单一类别（即体育类）中的大量应用。我们对谷歌应用商店中超过两千款体育应用进行了实证研究。通过人工分析研究这些应用的特征（如目标体育类型和主要功能），通过主题建模分析用户评论中的话题，并通过用户评分与情感分析探究导致用户负面评价的因素。研究结论表明，分析特定类别应用（如体育类）能比跨类别分析提供更具体的见解，同时仍可适用于大量（如数万级）应用。此外，作为快速增长且竞争激烈的市场，体育类应用为未来研究提供了丰富机遇，例如探究数据科学或机器学习技术在软件应用中的整合，或研究影响应用竞争力的因素。