Let me answer the question asked by Asimor. According to Apple's Self Service Repair page, repairing it yourself using genuine parts and tools and following the manual does not automatically void the warranty on the rest of the device. What is not covered by the warranty is damage caused by yourself while repairing, for example accidentally tearing the internal screen cable or breaking the hinge, then you will be considered responsible for that part. After replacing, there is one more step to run System Configuration for the device to receive new components. If ignored, the device will report unknown components and some features such as Touch ID may not run. With the iPhone Duo, the inner screen and hinges are quite fragile, so unless you are familiar with opening the device, I think it is safer to take it to Apple or an authorized center. In Vietnam, this program is not yet available, and components for Duo are not yet sold, so temporarily this document is most useful for workers and people who like to learn about machine structure.