You can use Pop Pay As You Go (PAYG) on your Android smartphone with Google Wallet, and use it on Metro in the same way that you’d use a Pop PAYG smartcard.
Just add a Pop PAYG card, which you’ll find in the list of Public Transport cards, with value loaded, into your Google Pay Wallet. Unfortunately there is not a facility to load an existing Pop PAYG card to Google Pay.
Then simply touch in and out with your phone at gates and validators at Metro stations. Google Wallet automatically deducts the fare from the Google Pop PAYG card and applies the Pop PAYG fare cap. Current Pop Pay As You Go Metro fares can be found here
Please note the Pop PAYG on Android can only be used on Metro, and can't be used on the Shields Ferry or local buses.
The Shields Ferry and local buses use different types of ticketing infrastructure to Metro, which aren’t currently configured to accept Pop PAYG on Android, but we’re working to introduce it in the future.