Poor cellphone coverage in supermarkets and malls could become less of a bugbear.
Supermarket operator Foodstuffs is trialling "cellsites in a box" provided by Vodafone that can be mounted on walls or stuffed into cupboards to cheaply plug gaps in mobile coverage.
Foodstuffs manages the New World and Pak 'n Save supermarket chains.
Vodafone spokeswoman Michelle Baguley said Foodstuffs' North Island co-operative was testing Vodafone's "small cells" at their head offices, but Vodafone envisaged they could be installed in semi-public places such as supermarkets, malls and cinema complexes.
The idea was that Vodafone would pay for small cells to be installed, she said.
The devices weigh about 10 kilograms and can carry up to 180 simultaneous phone calls, as well as mobile data traffic, the company said.
Telecom spokeswoman Kate Woodruffe said Telecom had also been testing small cells with its customers and "had a number of small cells at Gen-i client sites around the country, installed 18 months ago as part of an extensive pilot".
"These small cells are currently switched off while we complete the necessary upgrades for our commercial small-cell environment, due to go live later this month," she said.