Uber does not provide a way to tip via the app. Uber’s offical word to passengers about tipping = ” You don’t need cash when you ride with Uber. Once you arrive at your destination, your fare is automatically charged to your credit card on file — there’s no need to tip.”

The driver’s app does not send your destination UNTIL the driver confirms you are in the car and starts the trip. This applies to both Lyft and Uber.