Google has revealed a major expansion of its Android Pay system, letting people pay using it from apps.

The firm boasted there are now over 1 million locations across the United States that already accept tap and pay, with more being added 'every day'.

It will now allow let people use the same system for in-app purchases - as Apple does with its rival Pay system.

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The firm boasted there are now over 1 million locations across the United States that already accept tap and pay, with more being added 'every day'.

CAN YOU USE IT? Android Pay works with all NFC-enabled Android devices (running KitKat 4.4+), on any mobile carrier, at every tap and pay ready location across the US. Android Pay will support credit and debit cards from the four major payment networks: American Express, Discover, MasterCard and Visa. These cards are issued by many of the most popular US banks and credit unions, including American Express, Bank of America, Discover, Navy Federal Credit Union, PNC, Regions Bank, USAA, and U.S. Bank. Citi and Wells Fargo will be available in the next few days, Capital One is coming soon. Advertisement

'Since this Fall, we've seen millions of people set up Android Pay, and the vast majority of them are using tap and pay with their Android devices for the first time,' the firm said.

'Now we’re ready for the next step: We're working to bring Android Pay's simplicity and security to purchases within apps, and to people in more countries around the world.

'Starting today, you’ll be able to use Android Pay to speed through mobile checkout within many of your favorite Android apps in the US.'

Earlier this year it launched its competitor to Apple Pay - turning Android phones into a credit card.

The firm says it will give millions of people a new way to buy goods and services using their phones.

It was thought the payment system would launch alongside Google’s Marshmallow operating system, expected in October, but Google revealed it actually launches today.

It is a direct competitor to Apple Pay, and does almost exactly the same thing - except on Android phones.

'Today, we’re beginning to roll out Android Pay - the simple and secure way to pay with your Android phone at over one million locations across the US,' google said in a blog post.

'Android Pay also stores your gift cards, loyalty cards and special offers right on your phone.

'We’ll be rolling out gradually over the next few days, and this is just the beginning.

'We will continue to add even more features, banks and store locations in the coming months, making it even easier to pay with your Android phone.'

Google says the service will work at over one million locations across the US.

Existing Google Wallet users can access Android Pay through an update to your Wallet app.

It was thought the payment system would launch alongside Google’s Marshmallow operating system, expected in October, but Google revealed it actually launches today.

For new users, Android Pay will be available for download on Google Play in the next few days, and will come preinstalled on new NFC-enabled Android phones from AT&T, T-Mobile, and Verizon Wireless.

Google also emphasised the security of the system, which like Apple Pay, doesn't reveal a user's real card number.

'We know how important it is to keep your personal and financial information secure, so Android Pay is supported by industry standard tokenization.

'This means your real credit or debit card number isn't sent with your payment. Instead, we’ll use a virtual account number that provides an extra layer of security.

'As soon as you make a purchase, you’ll see a payment confirmation that shows where a given transaction happened, so it’s easy to catch any suspicious activity.'

Earlier this month a leaked McDonalds memo hinted the service may launch sooner.

The internal notice, spotted by Android Police, reads: 'This month, customers will be able to start using Samsung and Android mobile devices to pay for their orders.

'Samsung Pay begins August 21 and Android Pay begins August 26. Service procedures are the same as with Apple Pay.’

ANDROID PAY: HOW IT WORKS With Android Pay, you will simply have to unlock your phone like you normally do and place it near a merchant's contactless terminal, to make a payment. No app needs to be open and you will see a payment confirmation and get transaction details on your phone. With select retailers, loyalty points and special offers will be automatically applied at checkout. To buy online, you will be able to use the 'Buy with Android Pay' option. Android Pay will soon be accepted at over a million store locations across the US, and in over 1000 Android apps, Google said. 'And we’ll be adding more every day.' Advertisement

The Internal McDonald's notice reads: ''This month, customers will be able to start using Samsung and Android mobile devices to pay for their orders...Android Pay begins August 26. Service procedures are the same as with Apple Pay’

Users will simply have to unlock their phone like they normally do and place it near a merchant's contactless terminal to make a payment.

No app needs to be open and they will see a payment confirmation and get transaction details on their phone.

The service allows Android owners to load their cards onto their phone

The new Android Pay system can be used in over 700,000 retailers, the firm said, and will compete directly with Apple Pay. The image above shows reward points (left) and the 'Buy with Android Pay' button (right)

While select retailers, loyalty points and special offers will be automatically applied at checkout.

Android Pay will store a user's credit, debit and loyalty card details, so when they are in a shop, they will simply have to unlock their phone to authenticate a payment and tap their phone on an Android Pay terminal to buy goods.

Transaction details will be sent to the handset and some retailers will offer loyalty points for using it.

For online purchases, users will be able to hit a 'Buy with Android Pay' button to avoid having to enter their bank details and shipping address each time.

When it does eventually launch, Android Pay will be accepted at more than 700,000 store locations across the US, and in over 1,000 Android apps, Google said. 'And we’ll be adding more every day.'

Last month, Google confirmed its latest version of Android - 6.0 - will be called Marshmallow.