In a Tweet sent yesterday afternoon from the official Pokemon Go account, Niantic Labs confirmed that Apple Watch support will be coming soon. This feature was originally announced in September but has not been mentioned since.
This tweet may have been in response to a rumor from 9to5mac that claimed Niantic had ceased development for the Apple Watch version of Pokemon Go. The app currently has a watch device called Pokemon Go Plus which syncs to your phone through Bluetooth and will notify you of nearby events.
Niantic has not confirmed whether or not “soon” applies to 2016 or early 2017.