Apple's mobile phone system update will fix the problems of the previous version and add some functions, which will do more good than harm.
However, the upgrade of the mobile phone system depends on the configuration of the mobile phone.
For example, although Apple 4S supports the system upgrade of ios8, many users will get stuck after the upgrade.
When there is a system upgrade, users should not rush to upgrade. It is recommended to observe for a period of time, read more mobile forums, and learn about the upgrade of other users before deciding whether to upgrade.
Upgrade method:
Open "Settings".
Enter the setting interface and click "General".
In the common interface, click Software Update.
If the software update detects a new system, you can click Update and keep your phone fully charged. If the mobile phone system is already the latest version, there is no need to update it.