Yeah… I own OnePlus 5T smartphone (by Oppo Electronics) at last. OnePlus is famous with their clean and fast operating system. Yup, stock Android + few modification here and there. That’s it. So here is the guide to test all the hardware functions like LCD, camera, Wi-Fi, microphone, sensor when you got OnePlus smartphones / going to buy it at shop. In short, just bring up FactoryMode app to test. Should work on other OnePlus models like OnePlus One, 2, X, 3, 3T, 5 and my current 5T. Upcoming 6 and 6T should work too…