There was recently some confusion about the compatible devices listed on the app details page of an app, so I'll clarify things in case anyone else has the same question.
Right now, it's possible for a developer to upload apps to the store that include support for the fēnix 3 HR with the 1.2.2 SDK. This device is announced, but within the app store it's still in a special "upcoming devices" state. That means that the store will accept app submissions for the device, but the device is hidden to the public.
When a developer is logged into their account, they will see the fēnix 3 HR listed as a compatible device for their app if support for this device was included when the app was built. Anyone else viewing that app on the store will not see the fēnix 3 HR listed as compatible until we activate the device and move it out of its special "upcoming devices" state. This behavior is by design--we want developers to be able to file the store with compatible apps so they're available when customers first receive these new devices. :)