This project is in collaboration with PDM Technology and aims to combine Augmented Reality and Digital Twin technology to create an application that can guide users in assembly or disassembly of machines. Machines are complex and difficult to assemble/disassemble, as many things can go wrong in the process, resulting in time and money wasted for individuals or businesses. To address this problem an Augmented Reality iOS app that guides users in assembly/disassembly by using Augmented Reality and Digital Twin was built in Unity. The app was tested with users and an expert from PDM Technology. The results showed that the user experience could use improvements, but that the Digital Twin and Augmented Reality aspects held great promise and were helpful to the users.