Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for evaluating interactions with a user interface of an application are disclosed. In one aspect, a method includes, for each of a plurality of different user sessions of a native application, accessing frame bundles that each include data representing content presented by a frame of a user interface of the native application at a given time. Each frame bundle includes at least a portion of a view tree of the native application used to generate the user interface at the given time and data specifying content presented by each view of the portion of the view tree. Based on the frame bundles, playback data are generated that present visual changes of the user interface corresponding to changes to the view trees.