Reading a website is not enough to say you've read the paper; reading the app is, according to News Corp chief executive Robert Thomson.

He says the same editorial value of print could be transferred to digital products such as tablet editions of newspapers.

"In the case of the (Wall Street) Journal, we were sitting down talking about how should we make the app look and we were playing with it and working on what the interface should be," Thomson told the UBS Media and Communications conference in New York.

"The one thing we agreed on is that if you were at Goldman Sachs and you were sharing an elevator ride with Lloyd Blankfein and Lloyd said 'did you read the Journal this morning?' if you had read the iPad app you could say, absolutely.

"Whereas if you've just read the website... it's pretty hard to say 'I've read the Journal this morning'. That sense of completion, of closure, conceptually and psychologically, it's really important, and commercially, it's worked for us."

But he says print advertising remains effective as a premium product, and had increased in value during a period of rapid digital expansion, and "retained unique value for advertisers. The relative value of print to certain clients in a digitally discursive age... is increasing."

Thomson says the biggest challenge for newspaper companies will be monetising content on mobile: "It's a small canvas, and a compelling canvas, and if you take the subway in the morning a lot of people are looking at their phones.

"How do you monetise it, given the canvas is smaller? What is the right format for headlines? How big should images be? All these things are really up for grabs," he said.

News Corp had "a significant advantage" in growing new acquisitions such as online real estate business Move, as a result of the "natural marketing platform" the company had through its media assets.

On Australia, he said that that while there was a lot of uncertainty in the economy, he liked the trajectory of the news business in the country: "The team there under Julian Clarke and Peter Tonagh, really has done a wonderful job of reconnecting with advertisers, sorting out the digital strategy, bringing new energy to the business," he said.

First quarter EBITDA had seen an unexpected increase, year on year: "With the Australian dollar weaker, that is generally good for the Australian economy," he said.