Vodafone is defending its mobile network against criticism from its most outspoken customer -- Auckland Mayor Wayne Brown.

In an interview with Newstalk ZB's Mike Hosking Breakfast, Brown revealed what's prompting his efforts to get Auckland's mobile blind spots fixed.

"What prompted that was I was walking across Hopetoun Bridge, just below my apartment, where I can see Sky Tower, and I went down to one dot [on my phone].

"That's when I realised why they've changed Vodafone to One because that's the number of dots you get when you're walking across the bridge."

Vodafone Spokesman Matt Flood said many factors can affect a customer's coverage.

"We were first to launch 5G in Aotearoa and are rolling this new technology out to dozens of cities and towns across the country.

"In built up areas like Auckland, coverage can be impacted by factors like buildings, other physical obstructions and congestion."

Brown said he'd also spoken to other people who reported similar experiences with their mobile providers in other parts of the Auckland region.

"Sometimes they need to be reminded that once you've got it and you're making money, you still have to keep investing to keep people happy."

Flood said the company had invested close to a billion dollars over the last three years to improve its Smart Network.

He said the company would welcome further discussion with Brown, on options to accelerate the building and upgrading of new mobile sites.

"This could include access to council land and buildings for network equipment, help with road closures for development works, ensuring new developments include provision for cell site space or speeding up council processes that govern how we deploy telecommunications technology.

"We look forward to engaging with the Mayor and new council to further discuss these and other areas of collaboration in the near future."