4 Reasons Not to Install watchOS 4.3 & 8 Reasons You Should

Don't Install If You Aren't Ready for iOS 11.3

You need to install iOS 11.3 to install watchOS 4.3. You cannot do it without the other and if you downgrade to iOS 11.2.6 you may have issues using your Apple Watch without iOS 11.3. 

Check out our reasons to install iOS 11.3 and reasons not to, do your homework and then decide if you are ready to upgrade to iOS 11.3. That update takes a lot less time than the watchOS update does. 

Once you are sure you are ready for iOS 11.3 full time, and don't plan to downgrade, it's OK to proceed with your watchOS 4.3 installation.