"I was a surprised to get to the finals, really, because I'm a relative amateur. I'm just this new guy that's never done anything before."
Pinkham said he could not disclose details about the app, for commercial reasons, but that his winning app came from observing customers at checkout.
"The idea is transferring money between a customer's accounts," he said. "The problem is that sometimes people don't have enough money in their account to pay for their groceries. My idea is a straightforward approach, and was inspired by Westpac's own CashTank app."
Pinkham said he was now looking for a new job as a software developer.
The other winners are David Arnold from Tauranga, and Wellington pair John Jackson and Justine Polkinghorne.
The winning apps were chosen according to their ease of use, quality of user interface, and security, speed, and originality.
Each of the winners takes home $10,000 in cash and Westpac will pay $50,000 to have the apps developed as part of a royalty-free, exclusive licence for New Zealand and Australia.
They also retain the intellectual property to leverage their completed app internationally.
Simon Pomeroy, Westpac head of digital banking, said the objective was for developers and designers to use their experience as bank customers to identify a service or process they thought could be done quicker and faster via a mobile app.
"The quality of entries that were submitted exceeded our expectations and showed that the innovation in this space in New Zealand is world class," Pomeroy said.
"We are very excited by the three projects and believe there is international potential amongst them."
Pomeroy said Westpac was now preparing to launch an international app challenge.
