Further Reading: http://www.forbes.com/sites/amitchowdhry/2015/04/21/whatsapp-voice-calling-ios/ and http://www.macrumors.com/2015/04/21/whatsapp-gains-voice-calling/

„WhatsApp, the popular mobile messaging service owned by Facebook, has released a major update to its iPhone app today. The update includes the highly-anticipated WhatsApp Calling feature, which rolled out to every Android user late last month. The WhatsApp Calling feature is comparable to Skype and the FaceTime Audio service on iOS. Data charges may apply while using the WhatsApp Calling feature.

“Call your friends and family using WhatsApp for free, even if they’re in another country. WhatsApp calls uses your phone’s Internet connection rather than your cellular plan’s voice minutes,” said WhatsApp in its app update description. 

Unfortunately, The WhatsApp Calling feature is rolling out slowly so you may not see it right away. The new calling feature should be available for every iOS user within the next few weeks. Prior to launching WhatsApp Calling for Android, the messaging company ran a lengthy beta test.

WhatsApp version 2.12.1 also includes an iOS 8 share extension, a quick camera button in chats, the ability to edit your contacts right from WhatsApp and an option to send multiple videos at once. You can also crop and rotate videos before sending them. The iOS 8 share extension lets you share photos, videos and links to WhatsApp from other apps. And the quick camera button lets you seamlessly capture photos and videos or choose a recent camera roll photo or video.

How does WhatsApp Calling for iOS work? If someone calls you through WhatsApp, you will see a push notification from the messaging service showing who the call is from. Once you answer the call, you will notice that there are options to mute the call or put it on speakerphone. You can also send a message to the person calling you. If the WhatsApp Calling feature for iOS is similar to the Android app, then you will see a Calls tab that has a list of your incoming, outgoing and missed WhatsApp calls. Personally, I do not have access to WhatsApp Calling for iOS app yet.

Launched in 2009, WhatsApp started out as a simple group text messaging app. Four years later, WhatsApp added a voice messaging service. And then Facebook acquired WhatsApp for $19 billion in February 2014. Several months ago, WhatsApp launched a desktop client called WhatsApp Web — which you can activate with an Android, BlackBerry, Windows Phone or Nokia S60 device.

Earlier this month, WhatsApp hit 800 million monthly active users. WhatsApp has been adding about 100 million monthly active users every four months since August. In January, WhatsApp hit 700 million monthly active users. WhatsApp now has more users than every other messaging app, including Facebook Messenger. It took Facebook about 8 years to hit 1 billion users. Facebook now has about 1.4 billion monthly users and Facebook Messenger has roughly 600 million users.“

„After promising to deliver voice calling capabilities back in 2014, WhatsApp has finally delivered, introducing voice over IP features in its latest update. With the new version of the app, it’s possible for WhatsApp users to call friends and family directly within the app using a Wi-Fi or cellular connection at no cost.

The introduction of voice calling to the Facebook-ownedWhatsApp app puts it on par with Facebook’s other messaging app, Facebook Messenger, which gained voice calling back in 2013. It also allows the app to better compete with other iOS-based VoIP calling options like Skype and FaceTime Audio.

Today’s WhatsApp update also brings a few other features, including the iOS 8 share extension for sharing videos, photos, and links to WhatsApp from other apps, contact editing tools, and the ability to send multiple videos at one time.

What’s new
-WhatsApp Calling: Call your friends and family using WhatsApp for free, even if they’re in another country. WhatsApp calls use your phone’s Internet connection rather than your cellular plan’s voice minutes. Data charges may apply. Note: WhatsApp Calling is rolling out slowly over the next several weeks.

-iOS 8 share extension: Share photos, videos, and links right to WhatsApp from other apps.

-Quick camera button in chats: Now you can capture photos and videos, or quickly choose a recent camera roll photo or video.

-Edit your contacts right from WhatsApp.

-Send multiple videos at once and crop and rotate videos before sending them.

WhatsApp can be downloaded from the App Store for free. The new WhatsApp calling feature will be rolling out to users over the next few weeks.“