Disclosed herein are systems, methods, and software for attaching applications to a computing device based on a file type selection. In one example, a method for operating an application attaching system to dynamically make applications available to a computing device includes identifying an application attach triggering event based on a file selection of a certain file type on the computing device. The method further includes, in response to the application attach triggering event, identifying an application within an application volume based on the certain file type. The method also includes attaching the application volume to computing device, and associating the application to the certain file type on the computing device.