How to download the watchOS 3 beta for developersInstalling the watchOS 3 beta is more complex than an iOS or OS X beta, but it's also for developers only.
There's yet to be a public beta for watchOS the way there has been for iOS and OS X and that's okay—the process for installing the software is more complicated and really meant for developers, not consumers. You need to install a certificate on your Apple Watch, then download the software to your iPhone running iOS 10 beta, transfer it across, and get it up and running. It's not hard, but it does take patience and you may have to troubleshoot.
Warning: watchOS 3 is a developer beta. You can't go back without significant help from Apple. You may love Activity and other data. So, if you're not a developer and you don't need the beta to test apps you intend to launch as soon as possible, stay away. Apple will release it to the public this fall.
How to install the watchOS 3 beta certificate
How to install watchOS 3 on your Apple Watch
How to downgrade to watchOS
How to instal...
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How to download the watchOS 3 beta for developers
