Uber is running a promotion for $10 off your next ride, good through May 31st. All you have to do is log into your app, go to the promotions tab and enter the promotion code ANDROIDPAY. No this does not require you to hook up to Android Pay at any point, just enter the code and you get $10 off your next ride, and for me, that's pretty much 2/3 of a normal Uber ride in Phialdelphia using UberBlack.
While Uber often runs promotions, see American Airlines, IHG Hotels, and more. These are often focused on getting new riders to ride with Uber. The Android Pay promotion is one that applies to current users too, so it's a bit of a bonus scenario for current users.
Make sure to jump on in at your next chance and grab your free $10, I never complain about free money.