I personally tested 5. of different devices with my friends, mainly because the domestic software was not actively updated to be compatible with 5.. The application of 5. is bound with lib, and many software signature conflicts can't be installed at the same time, such as Taobao and Alipay, some software can't be opened at all, such as 1236, and some software functions are damaged, such as lbe's root operation and SMS recovery of Baidu cloud backup.