Popular mobile messaging service WhatsApp is now bringing its voice calling feature to the iPhone. WhatsApp for iOS received an update Tuesday, which implements the calling feature. Users can download the new version on the Apple app store now, but WhatsApp will roll out the feature to current users over the next few weeks.

Android users have had the voice calling feature on WhatsApp for some time. WhatsApp allows users to make calls through the internet connection on their phone rather than through the device’s voice plan, much like the calling features on other messaging apps like Skype or FaceTime.

Calling someone on WhatsApp will prompt the app to launch when a call is coming in, similar to how a phone dialer app launches when receiving a direct voice call. While on a WhatsApp call users can mute calls or put the users on speakerphone. Users can also send messages or media while on a call.

On Android and now on iOS, WhatsApp offers free voice calling for one year, after which it charges $0.99 per year. In addition to voice calls, WhatsApp users can send messages, pictures, audio notes and video messages.

WhatsApp is owned by Facebook and has over 800 million monthly active users. In comparison, Facebook’s own messenger service has about 600 million users.

Another recent WhatsApp update allows users to back up their conversations, contacts, photos, music and other data to Google Drive.

WhatsApp also has plans to make its voice calling feature available to Windows and BlackBerry phones. Because of the nature of the app, being tied to a device’s phone number, WhatsApp is not available for tablets or Wi-Fi only devices.