Google users will find it easier to make on-the-go payments with their Android devices starting today, thanks to the help of a Google Payment API (application programming interface) announced earlier this year.

The API enables online payments via a variety of Google services, including Google Play, YouTube, Chrome, and Android Pay. It works by accessing the payment card details a user has saved on those and other Google services, and sending that information securely to the merchant.

Among the apps supporting Google payments are Instacart, Kayak, and Wish, along with others like Dice in the U.K. and iFood in Brazil. Additional merchants are expected to come on board soon, including Airbnb, Deliveroo, Papa John's, and StubHub.

Today's Google announcement comes on the heels of yesterday's news from Apple Pay vice president Jennifer Bailey, who revealed at the Money 20/20 conference in Las Vegas that Apple will soon have its payment service available in 20 countries, covering 70 percent of the global payment card market.

'Quick-Click' Purchasing

The new Pay with Google service (pictured above) is aimed at reducing the hassles many consumers currently encounter when trying to make payments online, said Pali Bhat, Google's vice president of product management, payments.

"If you've ever paid for something on your phone or tablet, you know just how frustrating checkout can be," Bhat wrote in a blog post today. "Maybe you had to fill in a bunch of forms. Maybe your session timed out. Maybe you encountered an error and had to start all over again."

Bhat added that the Google Payment API was designed to speed up the online checkout process, enabling purchases to be made with "a few quick clicks."

Buyers can choose which Google app to use for making payments, and designate which saved payment method they prefer to use. They can then quickly verify a payment using their security passwords or other authentication methods such as fingerprint ID.

Apple, Google Vie for Expanded Market Share

Upon announcing the Google Payment API in May, Bhat noted that Android Pay was available in 10 countries, with plans to expand soon into other markets including Brazil, Canada, Russia, Spain, and Taiwan.

Apple Pay is also moving into new markets, according to Bailey, who said at the Money 20/20 conference that the service will arrive in four new countries over the next few days: Denmark, Finland, Sweden, and the United Arab Emirates. In the U.S., Apple Pay now has a presence in more than half the country's retailers, she added.

The payment services provider First Data today also announced that it will begin offering its Clover Go mobile card reader/payment device at and Apple retail stores in the U.S. in the coming weeks.

According to the latest statistics from the payments industry site, nearly one-fourth (24.5 percent) of mobile phone users in the U.S. have tried Apple Pay as of June, while 10.6 percent said they have tried Android Pay as of March. Of Apple Pay users, 18.3 percent said they use it "every chance I get," while 68.4 percent of Android Pay users agreed with that statement.