Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for indexing application pages of native applications that operate independent of a browser application on a user device. In one aspect, a method includes instantiating a virtual machine emulating an operating system of a user device; instantiating, within the virtual machine, a native application that generates application pages for display on a user device within the native application; accessing, within the virtual machine, application pages of the native application, and for each of the application pages: generating application page data describing content of the application page, the content described by the application page data including text that a user device displays on the application page when the user device displays the application page; and indexing the application page data for the native application in an index that is searchable by a search engine.