Apple has released the latest version of the watchOS system. Software 7.0.3 is described as build 18R410 and is only available for Apple Watch series 3 watches.
In order to install the watchOS you have to run the Watch application on your iPhone, go to General and Upgrades respectively. To upload an update, you need to connect the watch to the charger and have the battery at least 50 percent charged.
The update is also available from the watch. To do this you need to enter Settings, General and Software Updates respectively.
Before installing a new watchOS, we recommend a backup. Please note that this is done with the iOS copy.
watchOS 7.0.3 contains improvements and bug fixes, including an issue where Apple Watch Series 3 may unexpectedly restart for some users.