Disaster support mobile apps play a central role during emergencies in conveying timely alerts to communities and providing recovery guidance. Their importance continues to grow as climate change increases the frequency and intensity of disasters, and as mobile devices become a primary information source for most people. However, despite their critical role, there has been limited systematic investigation into how these apps are designed and how users experience them in real-world contexts. This paper presents a large-scale empirical study of disaster support mobile apps aimed at addressing this gap. We investigated 44 apps available on the Google Play Store and the App Store and analyzed 28,161 user reviews to understand common functionalities, user expectations, and challenges encountered during use. Our feature analysis identifies 13 core capabilities spanning the stages of preparation, response, and recovery of the disaster lifecycle. Topic Modelling revealed 18 topics, with the highest discussions focusing on app alert functionality, the use of maps, and monetary transactions. Sentiment analysis revealed that while 53.09% of users provided positive feedback, 24.30% expressed negative opinions, and 11.25% remained neutral. It also showed that signup/signin issues, network problems, and app crashes were the most frustrating to users. These impacted user safety by preventing access when it mattered most. Our findings emphasize the need to approach disaster apps as safety-critical and human-centred systems, where reliability and ease of use are essential. We provide practical recommendations to support developers and emergency agencies in improving the dependability and accessibility of future disaster support apps.

翻译：灾害支持移动应用在紧急情况下发挥着核心作用，能够向社区传递及时警报并提供灾后恢复指导。随着气候变化加剧灾害的频率与强度，以及移动设备成为大多数人获取信息的主要来源，此类应用的重要性日益凸显。然而，尽管其作用关键，目前对于这些应用的设计方式及用户在实际场景中的使用体验仍缺乏系统性研究。本文通过一项大规模实证研究填补这一空白，对灾害支持移动应用进行了深入分析。我们调查了Google Play商店和App Store中的44款应用，并分析了28,161条用户评论，以理解其常见功能、用户期望及使用过程中遇到的挑战。功能分析识别出覆盖灾害生命周期准备、响应与恢复阶段的13项核心能力。主题建模揭示了18个主题，其中讨论最集中的是应用警报功能、地图使用以及货币交易。情感分析显示，53.09%的用户给予积极反馈，24.30%表达负面意见，11.25%保持中立。分析还表明，注册/登录问题、网络故障和应用崩溃最令用户感到困扰，这些缺陷在关键时刻阻碍访问，直接影响用户安全。我们的研究结果强调，必须将灾害应用视为安全关键且以人为本的系统，其可靠性与易用性至关重要。我们提出了实用建议，以支持开发者和应急机构提升未来灾害支持应用的可靠性与可访问性。