To install the watchOS 7.1 beta, developers need to download the proper configuration profile from the Apple Developer Center. Once the profile is in place, the watchOS 7 beta can be downloaded through the dedicated Apple Watch app on the iPhone by going to General > Software Update.
To update to the new software, the Apple Watch needs to have 50 percent battery life, it must be placed on the charger, and it must be in range of the iPhone.
There were no new features discovered in the first two betas of watchOS 7.1, so we don't yet know what new additions may be included in the update. It likely focuses on under-the-hood improvements and bug fixes for issues that weren't able to be addressed in the initial watchOS 7 release.
If new features are found in the third beta of watchOS 7.1, we'll update this article. watchOS 7.1, like watchOS 7, is compatible with the Apple Watch Series 3 and later.