to a wifi controller intending to use my voice to open the garage door as I drove into the driveway. I wanted to simply say, "Alexa, open the garage door". That command will work on my Echo, Echo Dot, etc inside the house, but I can't do it from my phone or the Echo Auto. bummer.

Unfortunately, Alexa doesn't work on any cell phone to open wifi-enabled locks because it's a "security issue". That's a bummer.