Emanuel Kalafatelis, a partner at the research company, said this showed we were becoming more internet savvy and that smartphones, laptops and tablets were "definitely the way of the future".
He expected PCs to eventually disappear as people moved towards laptops and tablets.
And he said the penetration of smartphones - one in every two people over 18 - was "remarkable" given the short time they had been around.
"We really do depend on them and people are saying they're using them more frequently than they were a year ago."
Helen Griffen is one iPhone user who finds it hard to go without.
After four years of owning iPhones, she decided to give it up after her most recent one broke when she dropped it. But having relied on a smartphone for so long, being without the device has been a struggle for the engineer.
Now she can't check her emails, the weather or what's happening on Facebook, or transfer money. Worst of all her messages aren't in a stream.
Vodafone told her it would cost $400 to look at her smartphone and find out what needed to be fixed and Ms Griffen decided it wasn't worth it.
"But I'm now honestly considering buying another one after using this brick," said the 26-year-old.
An American survey showed this week that most teenagers use their phones to access the internet, with one-quarter of them going online mostly on their mobile device.
Seventy-eight per cent of US teens have cellphones, and 47 per cent of those own smartphones, according to the survey by the Pew internet Project with Harvard's Berkman Center for internet & Society.
"In many ways, teens represent the leading edge of mobile connectivity, and the patterns of their technology use often signal future changes in the adult population," the researchers wrote.
"Teens are just as likely to have a cellphone as they are to have a desktop or laptop computer. And increasingly these phones are affording teens always-on, mobile access to the internet, often serving as their primary point of access."
Tablets are also gaining ground, with 23 per cent having access to one of these devices, the survey found.
Mr Kalafatelis said age was the most discriminating factor when it came to technology.
"There aren't really any [variables] by gender, region or whether one's living in an urban area or non-urban centres.
"I think most of the differences are by age and then by income."
What we use
What New Zealanders have:
Laptop or notebook: 66 per cent
PC: 61 per cent
Smartphone: 48 per cent (Men: 51% / Women: 45%)
Another type of cell phone: 48 per cent
Tablet or iPad: 29 per cent
None of these: 4 per cent
If you could have only one of these types of devices, which one would it be?
My PC: 19 per cent
My laptop or notebook: 29 per cent
My tablet/iPad: 4 per cent
My smartphone: 28 per cent
My mobile (other): 19 per cent
Frequency smartphones are used:
Every day: 86 per cent
Most days (5 or 6): 4 per cent
Every other day (3 or 4): 3 per cent
Once or twice a week: 2 per cent
Less than once a week: 4 per cent
Don't know: 1 per cent
Frequency of smartphone use compared to last year:
More frequently: 41 per cent
Less frequently: 8 per cent
About the same: 40 per cent
Didn't have one last year: 7 per cent
Don't know: 1 per cent
What we're using smartphones more frequently for:
Send and receive calls: 79 per cent
Send and receive texts: 83 per cent
Send and receive data files, pics or other attachments: 66 per cent
Connect to the internet: 84 per cent
None of the above: 1 per cent
What apps on smartphones or tablets do you use the most:
Social (eg Facebook): 79 per cent
Apps for referencing or information (eg maps): 76 per cent
News and weather apps: 70 per cent
Apps for games and other entertainment (eg movies): 70 per cent
Business/banking apps: 54 per cent
Apps for Govt agencies: 16 per cent
Other: 1 per cent
Don't use apps: 6 per cent
Sourced from Research New Zealand
