Apple has released a software update watchOS 4.0.1 to Apple Watch Series 3 with cellular users. The new update particularly focusses on fixing a Wi-Fi connectivity issue some Series 3 models with LTE experienced. The issue prevented the devices from connecting to LTE.
Apple's release notes said, "watchOS 4.0.1 fixes issues that in rare cases were causing Apple Watch to join unauthenticated (captive) Wi-Fi networks, such as those found in public places like coffee shops and hotels, which direct the user to a web page before the network can be accessed."
— Rene Ritchie (@reneritchie) October 4, 2017
To download watchOS 4.0.1, go to the Watch app on your iDevice and navigate to General, then Software Update. Your Apple Watch Series 3 must be connected to Wi-Fi, placed on its charger, and have at least 50-percent battery life to download watchOS 4.0.1. Apple is also beta testing watchOS 4.1 which would be available next year.
Additionally, Apple is also bringing LTE music and radio streaming to its Apple Watch Series 3. Currently, users must sync their music to their watch to listen on the go.