The Appium + Sauce Labs Bootcamp discusses testing hybrid apps and mobile web applications using Appium. Hybrid apps can be a mix of native and web-based components, while mobile web applications run in a browser on the device. Appium supports two contexts: native and webview, which determine how commands are interpreted and executed. The native context executes against the device vendor's automation API, allowing access to views and elements through name or accessibility id, as well as interacting directly with the device. In contrast, the webview context uses standard WebDriver commands to interact with web application elements through CSS selectors or other web-specific locators. Switching between contexts can be done using a method that takes the string name of the desired context. Once in the webview context, Selenium commands can be used to automate web applications. The native context provides access to an xml document describing the view's elements, not the HTML even if there is HTML being rendered. Querying contexts allows choosing from available contexts and switching between them. Additionally, multi-tabbed web browsers are accessible through the window commands in a webview context.