This paper introduces the Lang-Track-App, a smartphone application and backend system to aid second language acquisition researchers in implementing the experience sampling method (ESM). Surveying research participants with the Lang-Track-App multiple times per day can yield exceptionally rich data that can be analyzed in multiple ways. This article explains the different Lang-Track-App components and describes workflows for both researchers and participants. To demonstrate the step-by-step implementation, we present a recent study of language use in study abroad as a test case in which we used the Lang-Track-App to collect ESM data about frequency and qualitative aspects of language use. A selection of findings from this study highlights the richness of ESM data and how they can be analyzed at various levels. Researchers wishing to use the Lang-Track-App to implement the ESM in their own research can access the full open-source code and documentation via GitHub (https://github.com/HumlabLu).

中文翻译：

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Lang-Track-App：在第二语言习得研究中实施经验采样方法的开源工具

本文介绍了 Lang-Track-App，这是一款智能手机应用程序和后端系统，可帮助第二语言习得研究人员实施经验采样方法 (ESM)。每天使用 Lang-Track-App 多次调查研究参与者可以产生异常丰富的数据，并可以通过多种方式进行分析。本文解释了不同的 Lang-Track-App 组件，并描述了研究人员和参与者的工作流程。为了演示逐步实施，我们提出了最近的出国留学语言使用研究作为测试案例，其中我们使用 Lang-Track-App 收集有关语言使用频率和定性方面的 ESM 数据。这项研究的一系列结果强调了 ESM 数据的丰富性以及如何在不同层面上分析它们。