WhatsApp's Co-founder Is Upset About Apple's New Messaging Features

Apple Senior VP Craig Federighi speaks during the Apple Worldwide Developers Conference at the Moscone West center on June 2, 2014 in San Francisco.Justin Sullivan/Getty Images

In today's Worldwide Developer Conference, Apple rolled out a few new features for its iMessage app, including audio and video messages, and group messaging capabilities.

Not all tech junkies were happy about Apple's innovation. Co-founder of WhatsApp, Jan Koum, tweeted out this message after Apple's announcement:

For those of you who don't use WhatsApp, Apple just added features that WhatsApp users have been able to use all along. WhatsApp users could always record audios and videos, and share location data easily through messages.

WhatsApp has more than 500 million users. Apple's intention is clear-it wants all iPhone users to use its in-house app, instead of downloading and using other app, such as WhatsApp-which was purchased by Facebook for $19 billion, Snapchat, Facebook Messenger, and WeChat.