According to the query of Yangtai. com, the miui test is orange, Friday. Because the initial system update of Xiaomi's mobile phone is updated and maintained every Friday afternoon, and the MIUI that Xiaomi just started is an orange icon, it is called orange Friday. The function update of the development version is relatively slower than the experience version, but much faster than the stable version. It is also a long-term test for future stable versions. Through the function addition and iteration of the development version, as well as user feedback and survey, MIUI can continue to launch a better "Orange Friday". So orange Friday is the upgrade time of Xiaomi MIUI version.