New online Instant Kiwi games could provide more temptation for problem gamblers, fears their support foundation.
Digital game tickets can now be bought via the Lotto app. Users can spend up to $50 a week.
Problem Gambling Foundation spokeswoman Andree Froude told Newstalk ZB's Nadine Higgins the spending restrictions do not go far enough.
"Even $50 a week for some people can be a lot of money. And the thing is the accessibility, you can carry it around in your pocket 24/7."
She said young people can get around age restrictions.
"It is much more addictive than buying a Lotto ticket and it is just so accessible. We don't want to see people getting themselves into trouble.
"It's a very different type of gambling to purchasing a Lotto ticket. The instant gratification thing is a real trigger for some people."
Tickets range in price from 50 cents to $5.
Froude told Newstalk ZB such games can be highly addictive.
"It's a very different type of gambling to purchasing a Lotto ticket. The instant gratification thing is a real trigger for some people."
Users of the app must be aged 18 or over.