Techniques are described for dynamically determining the flow of screens to be presented in a user interface (UI) of an application executing on a computing device, based at least partly on a detected presence of a user device (e.g., a portable computing device) in a particular geographic area. Area designation data is transmitted to, and stored on, a user device. The area designation data can describe a geofenced area and/or beacon signals. In response to determining that the user device is in the geographic area indicated by the area designation data, the user device may transmit an alert signal that causes an interface flow to be dynamically determined and executed for an application executing on the computing device that is separate from the user device.