Optus has launched a contactless payment app which allows you to use your smartphone to make purchases.

Dubbed Cash, the new offering, in collaboration with Visa and Heritage Bank, uses near field communications and Visa paywave to enable payment of purchases below $100 with a smartphone.

It works like a Visa Prepaid debit card. Customers can load up to $500 at any one time and make contactless purchases under $100 at any retailers that accept Visa payWave.

Customers need an Optus postpaid mobile account, a compatible Android smartphone, an NFC enabled SIM and the Cash by Optus app.

Optus mobile marketing vice president, Ben White, said there were already nearly one million Optus postpaid customers with compatible devices who could make purchases using Cash by Optus.

"We're the first Australian telco to launch a mobile payments app, and because it's compatible with many of the latest Android devices and can be linked to any Australian bank account, we've got a huge opportunity to bring this technology to a lot of people," he said.

Australians are leading the world for contactless payments with over 64 million Visa payWave transactions in September 2014.

In fact, more than half (55 per cent) of face-to-face Visa transactions in Australia are made using Visa payWave.

Visa head of emerging products, George Lawson, said Australians were clearly choosing more convenient ways to pay.

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"The rapid growth of contactless payments in Australia has set the right conditions to enable a mass shift to mobile payments," he said.

"We're excited to support Optus in its drive to provide a simple mobile payment experience for its customers."

Cash by Optus uses Visa payWave technology, which uses the international EMV chip standard, and provides some of the most widely adopted cryptographic security.

If you lose your phone your Cash by Optus account will be closed and you can request your balance to be returned. You can also cancel your account at any time or dispute transactions if you don't recognise them.

It is issued by Heritage Bank, which is responsible for the banking aspect of Cash by Optus.

Heritage Bank, chief executive, John Minz, said, Heritage Bank was a relatively small financial institution.

"But we're already recognised for our ability to deliver really creative and effective payment solutions for our corporate partners, particularly in the area of prepaid transactions," he said.

"The launch of Cash by Optus now also establishes Heritage as a leader in mobile payments. Our specialist expertise in this emerging area of payments reinforces our position as an enabler of innovative new services that the customers of leading Australian companies are seeking."

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