The first of Nintendo's smartphone games that it's making in partnership with mobile gaming giant DeNA will all be free-to-play, DeNA confirmed during an earnings briefing attended by The Wall Street Journal.

Miitomo

"Games currently in the pipeline are all free to play," DeNA CEO Isao Moriyasu said.

DeNA and Nintendo plan to launch five smartphone games before 2017. The first of these, called Miitomo, was expected to arrive before the end of the year but has now been delayed to March 2016.

Miitomo was previously confirmed to be free. However, during an investor briefing last month, Nintendo said other games might be pay-to-download further down the road.

Not much is known about Miitomo at this time, and WSJ reports that Moriyasu did not refer to it as a game, but rather more of an entertainment and communication platform.

A slide from DeNA's latest earnings report (below) sheds more light on the company's plans. Among other things, it shows that DeNA plans to monetize the Nintendo games through microtransactions. These will be "carefully decided based on user expectation and gameplay," though no specifics were shared.

Miitomo and Nintendo's other upcoming smartphone games will also tap into a new membership service that's being called Nintendo Account. This will use "a cloud-based data service to transfer game data between mobile games and console games." In addition, a new rewards program called My Nintendo is in the works, but no additional details were provided regarding that service.