"Harden" is a Progressive Web Application (PWA) for Ecological Momentary Assessment (EMA) developed mostly in R, which runs on all platforms with an internet connection, including iOS and Android. It leverages the shinyMobile package for creating a reactive mobile user interface (UI), PostgreSQL for the database backend, and Google Cloud Run for scalable hosting in the cloud, with serverless execution. Using this technology stack, it was possible to rapidly prototype a fully CRUD-capable (Create, Read, Update, Delete) mobile app, with persistent user data across sessions, interactive graphs, and real-time statistical calculation. This framework is compared with current alternative frameworks for creating data science apps; it is argued that the shinyMobile package provides one of the most efficient methods for rapid prototyping and creation of statistical mobile apps that require advanced graphing capabilities. This paper outlines the methodology used to create the Harden application, and discusses the advantages and limitations of the shinyMobile approach to app development. It is hoped that this information will encourage other programmers versed in R to consider developing mobile apps with this framework.

翻译："Harden"是一款主要用于R语言开发的生态瞬时评估渐进式网络应用，可在所有具备互联网连接的平台上运行，包括iOS和Android系统。该应用采用shinyMobile包构建响应式移动用户界面，PostgreSQL作为数据库后端，并通过Google Cloud Run实现云端无服务器可扩展托管。借助该技术栈，我们成功快速原型开发出具备完整CRUD（创建、读取、更新、删除）功能的移动应用，实现了跨会话用户数据持久化、交互式图表及实时统计计算。本文将该框架与当前其他数据科学应用开发框架进行比较，论证了shinyMobile包为需要高级图表功能的统计移动应用提供了最高效的快速原型开发方案之一。本文详细阐述了Harden应用的构建方法，并讨论了shinyMobile开发模式的优势与局限，旨在鼓励掌握R语言的其他开发者考虑采用此框架进行移动应用开发。