A Wellington tech firm Postr is hoping to raise more than $2 million to fund its growth plans overseas.

Postr works with telcos to allow Android users to get free data in exchange for advertisements on their phone lock screens.

The company was launched by Wellington entrepreneur Milan Reinartz? in 2014, and has since signed with Skinny Mobile in New Zealand, as well as telcos in Australia, Indonesia, and Germany.

Postr's next target is the Philippines and Portugal, it is also in discussions with telcos in South East Asia and South America.

Chief operations officer Roger Shakes said the business provided a "really interesting proposition in the advertising and mobile space".

"There's a really interesting value exchange in that if you are prepared to opt in and receive ads on your lock screen device, you are rewarded with free data.

"There is no incentive for the consumer or the subscriber to engage in any of the ads, it essentially operates like television where you watch television, see ads, and get content for free," he said.

"In this case, you subscribe and see ads on your lock screen device and in return a consumer gets free data."

The way businesses advertised had changed dramatically over the years, Shakes said.

"If you think about advertising generally, there's a shift from traditional television, radio and print, into the digital opportunity.

"And within that digital opportunity, mobile is one of the core growing areas and so brands want to be where consumers live, and consumers live on their mobile devices."

To date, about 250,000 devices have signed up.

One of the biggest challenges was operating the business globally, he said.

"We recognised quite early that we needed to be in markets where there is high Android use … and in order to do that we have to be close to those markets and be close to those clients.

"We have to be in their time zone and that's a challenge when you are in New Zealand and you want to be responsive, but it just means you have to find ways to press the flesh and respond in your time by having a presence on the ground."

Shakes was looking forward to further investment in growth, Shakes said.

"We set ourselves some lofty ambitions, as you can imagine, and I think realistically we'd like to partner with 100-plus telcos around the world within four or five years and have an audience through those telcos of several million."

(Stuff)