Google Pay is getting the ability to purchase transit tickets ahead of time and use them with NXP MiFARE terminals, with the Las Vegas Monorail being the first transit entity to accept this new method of payment. You'll have to buy the ticket ahead of time, but once you do, you can use Google Pay to skip the line and get through the turnstile. Any Android device with Google Services that can run Google Pay and has an NFC chip on board is able to be used in this manner, which includes most modern devices, and all mainline flagships from 2015 onward, save for the OnePlus 2, which skipped on NFC to cut costs because the feature still wasn't particularly popular at the time of its release. Furthermore, Google says that more transit authorities will be joining the effort in the near future.
Once you have your ticket bought and saved to Google Pay, using it works in much the same way as making any other purchase with Google Pay; so long as your phone is unlocked and its NFC chip is turned on, just tap your device on the terminal to use your ticket. It's worth noting that you don't need to have a payment method linked up to Google Pay in order to use this functionality; the purchased monorail ticket is treated as the form of an in-app purchase and will be scanned via NFC when you use the NXP MiFARE terminal.
Google has been pushing to make Android Pay, recently rebranded as Google Pay, more popular since its inception with a number of promotions and special events. Google Pay is accepted anywhere where Android Pay is since it's just a rebranded version of the same system. All the same, Google Pay is not the most popular or ubiquitous NFC payment solution on the market, which means that Google will have to keep working to get it accepted in all of the same places as Apple Pay, though it won't be able to compete with Samsung Pay due to the service's lack of the magnetic functionality that allows Samsung Pay to be accepted almost anywhere a normal credit or debit card would be.