One time the guy was just 3 blocks away so I walked to where his icon was, found the car, and banged on his window.
During a weekend trip to Orlando trying to get from our hotel to Disney it took 6 drivers until someone finally came to pick us up.
At least the price is given ahead of time and paid through the app. I once had a cab driver charge my card for $300 when I was borderline blackout drunk in Miami Beach trying to get back to mainland Miami. Didn't use the card reader in the cab either, he used something like a Square reader on his phone. Not exactly sure which one, I didn't piece together what he was doing was fishy until the next afternoon when some blurry memories started coming back and I called my bank.