WhatsApp — the hugely popular messaging app found on Android, the iPhone, Windows Phone, BlackBerry, and even Symbian — is now in the voice messaging business. On Tuesday, while also announcing that it now has 300 million monthly active users, WhatsApp began updating its apps to enable users to send voice memos to one another.

325 million photos shared each day

The voice messaging feature, which was first reported by AllThingsD, won't work like a phone call. Rather, it'll work more like more like a push-to-talk app, where a user can record a snippet of audio directly in the app and send it along to a contact in real time. WhatsApp has offered the ability to share audio files as attachments for months, but the voice messaging update allows users to see when the person they're communicating with has heard their recording, or if they're about to send a voice clip. And, in WhatsApp's case, users can respond in voice, text, photos, or video.

While voice is a new frontier for WhatsApp, the company has a track record of success in text and photo messaging. WhatsApp told The Verge in an email that its users currently send about 31 billion messages per day, 325 million of which are photos. To put that in a bit of context, in June the company said its users were sending about 27 billion messages a day and that it had about 250 million monthly active users. WhatsApp is growing, and voice might help the app find even more customers.