The fifth beta of iOS 11.3 released by Apple today is based on repairing Bugs as a whole, while maintaining the stability of the system. Some developers stated that after this beta version, the official version of iOS 11.3 will be finalized. Posted (expected to release the official version at the end of the month).
The reason why the official version of iOS 11.3 is so attractive to users, or its attractive features, Apple has previously promised that those users with iPhone downclocking can be manually closed after upgrading the official version of iOS 11.3, of course, you can also produce in the battery options. Look at the health of the device's battery. If it is particularly bad, the system will directly advise you to replace the battery.
So from the perspective of improving performance, iPhone 6, 6S, 7, and SE models must be upgraded (have been down-converted).
It is worth mentioning that iOS 11.3 will also bring some new features, such as uploading all iMessage and SMS to the cloud, business communication and so on.