It’s already integrated as part of the Fan Tiles, Battery Tiles, Label Tiles, and More! release! 
SmartThings has an official Z-wave Fan device handler which should be the new default for the GE Z-wave fans, Leviton 3-speed fans, and Honeywell Z-wave plus fan devices.
If you paired your fans before SmartThings released the new device handler, your devices may still be using the old dimmer style device handler. You can change the device handler in the IDE though.
What kind of fans do you have connected in SmartThings (and what device handler are they using)?
Edit: Note that a lot of community device handlers are still using the old Switch + Switch Level approach and haven’t updated to match the new Fan Speed capability.