I attempted to hail rides with Uber and Lyft using just my voice. Unfortunately, only Alexa and Siri got me cars, but with varying results.
After I said, "Alexa, ask Uber for a ride," she informed me an uberX was less than one minute away. To order it, all I needed to do was say "yes." However, I checked the Uber app out of curiosity, and it said an uberX was six minutes away. Similarly, Alexa said there'd be a 50 percent surcharge on Lyft, because "it's busy out there," but the Lyft app showed only a 25 percent increase.
When I told Siri, "I need a ride," she offered a choice of Lyft, Uber or a taxi, and I could complete the request by voice, using additional prompts.