The app has raised over $22,000 for the partnered charities - including Oxfam, Starship, Make-A-Wish and World Vision - since its launch in November 2013.
Little Lot is in talks with schools and universities to install the app across their computer networks.
"As the audience grows this will become a very attractive medium for brands,"
"We currently have around 4,000 - 4,500 active users, however moving forward we are really focusing on the computer apps for Windows and OSX," said Mr Hillier.
Little Lot struggled to sell its inventory so to keep the app content fresh, a lot of the adverts were free trials for new clients.
"It is taking quite some time to educate advertisers and media buyers of the qualities of our channel," said Hillier.
"As we grow and become more established, we will be able to sell more wallpapers. Until then we can only ask that our early adopters keep the faith and help us reach critical mass," he said.
Ruth Nichol, communications manager for Philanthropy New Zealand, said they welcome new initiatives like Little Lot as they provide another avenue for people give.
"Little Lot may not be the way of giving to charity in the future, but it is certainly one way of doing so, and it is part of the growing number of online-based giving platforms that are providing people with lots of different options to be generous."
Graduating advertising student and Little Lot user Janelle Collins thinks it is a great way to help out charities and can easily be sold to consumers as a simple way to donate.
It is an exciting model however I think charity will and should always be a mix of fundraising - individual and corporate philanthropy, payroll giving, online fundraising websites, events - it really depends on the charity.
"I like that you can give your screen up to advertising to raise money for charities, without having to do a whole lot.
"Being an advertising student I also like the fact it's utilising advertising in a way that isn't intrusive or demanding, but instead is interesting and often quite pleasant to look at."
Oxfam has been partnered with the app since its inception as the app allows them to offer their supporters another way they can donate, without emptying their wallets.
Oxfam's relationship fundraising manager Hannah Davies said the app had not increased the speed in which donations were coming in and had not changed Oxfam's methods of donation gathering due to its lack of momentum.
Fundraising Institute of New Zealand CEO James Austin said donating electronically is growing but will not sideline the conventional methods of fundraising.
"The key aspect about crowd funding and other electronic gifting is that it attracts new donors who are of a younger generation. They are the future donors. It will be a mistake though, to dismiss other forms of fundraising."
Hillier said it was not the intention of the app to replace existing fundraising methods, rather just another way for charities to engage with their supporters and generate contributions from them.
"It is an exciting model however I think charity will and should always be a mix of fundraising - individual and corporate philanthropy, payroll giving, online fundraising websites, events - it really depends on the charity."
Hillier said Little Lot's goal was to get the app to a point in New Zealand where it is raising five million dollars a year for the partnered charities.
