Smartwatch for Dex 4 w/Share--seeking info

I like to keep things simple, so only interested in using Dex receiver Share-to-Smartwatch. I use an iPhone so the iWatch is the easy choice, especially for when I upgrade and can drop the receiver. I’d rather go with the Fitbit Ionic. Can anyone tell me if I can use Share with Ionic, of Ionic is compatible with Dex 5/6 phone-watch reception, and how functionality of the watch face for monitoring BG compares to iWatch? Thank you!