2, the optimization is not big. In fact, Android optimizes a large number of resident process software, which is itself a big consumer of power and traffic. Just install it. The really good way to save electricity is to modify the settings to save electricity. Any power-saving software is a fool.
3. Some functions, such as boot process optimization, such as CPU frequency modulation, must have ROOT permission.
4. After 4.ROOT, you can upgrade by brushing the firmware package optimized by the third party (provided that you brush the recovery of the third party). If you have offset permission, you can also try to brush the official firmware package, otherwise the upgrade official must brush back to the official recovery to upgrade the phone online.
5. No, security has nothing to do with ROOT, but with the software you installed. If you install a Trojan horse, it will be more dangerous. So don't install the software indiscriminately, but install the software from a reliable source (try to download it from official website).
6. Forced frequency reduction and power saving may not necessarily reduce system performance. For example, you can reduce the CPU frequency of the mobile phone to a certain extent after it is turned off, and then rise back to the default frequency after it is turned on, so that the mobile phone will save a lot of electricity in the screen state; Startup performance will not be affected. Adjust the screen brightness or something, you can adjust it without ROOT, and ROOT can adjust the parameters of light sensitivity, but this requires a deeper understanding of firmware. In addition, don't expect how much system software can be deleted after ROOT. Most system software can't be moved, only the solidified software in the system can be deleted safely.
7. It will be more convenient after 7.ROOT, but it is really more convenient to brush the third-party recovery, and brush all kinds of streamlined and optimized third-party firmware after departure. Some optimized firmware can significantly improve the performance, capacity, power saving and speed of the mobile phone.
Note: it's not pasted, it's all handwritten, I hope it won't take seconds …