Jan Koum, the co-founder and chief executive of WhatsApp, also said during a speech at Mobile World Congress in Barcelona that he is hoping to grow the service to one or two billion users.
Mr. Koum said that the WhatsApp voice product would “focus on simplicity” as it has with its text-based messaging service.
He said that WhatsApp would first release a version of the voice service for Apple Inc.’s, iPhone and Google Inc.’s Android platforms, followed by services for Microsoft Corp.’s Windows Phone, as well as some phones by BlackBerry Ltd. and Nokia Corp.
“We want to continue to have that minimalistic approach to the product,” he said. “We at WhatsApp want to get out of the way and let people communicate.”
Mr. Koum added that the voice product would “use the least amount of bandwidth, and we optimize the hell out of it.”
Speaking about the Facebook acquisition announcement earlier this month, Mr. Koum said that the product wouldn’t change, stressing that WhatsApp would remain independent. He cited Instagram’s example, after the acquisition of the photo-sharing service by Facebook.
Mr. Koum said that WhatsApp was likely valuable to Facebook because “we both want to make the world more connected,” though Mr. Koum stressed that WhatsApp wanted to know “as little as possible” about its users, including details such as a user’s name.
“There are no plans to change anything that we do with the product today,” he said, using words like “minimalistic,” “utilitarian” and “uncluttered” to describe his philosophy.