Missing Uber and Lyft on Android Wear
I can suggest sideloading the Lyft app. Earlier versions of Lyft had Android Wear support, but it was later removed (for some reason).

Here's how to get Lyft on Android Wear watches:


Delete the Lyft app from your phone.
Allow downloads from unknown sources.
Download the Lyft APK version 3.50, the last version available on APKMirror to support Wear.
Sign-in to the Lyft app.
Wait a few minutes, then go into the Android Wear app on your phone. Scroll down to "Actions", then tap "Call a Car" and then tap "Lyft".
Now you can say to your watch, "OK Google, call me a car" and it will order a Lyft to your current location.
Turn off Lyft auto-updates in the Play Store: go to Lyft's page, hit the three dots in the top-right, and uncheck auto updates.


Note 1: The Lyft app will appear on your watch's launcher as well. For me, it didn't work initially (it crashed on launch for a few hours), but now I can order a car from that app as well, giving (me at least) two ways to order a Lyft from your watch.

Note 2: I'll be sending an email to Lyft asking them to add Wear support back to the latest version of the Lyft app.