iPhoneItalia says that VoIP calling is indicative for the app’s new look for the iOS 7.1, till the circular button ‘End Call’. The VoIP call makes the app displays the name of the caller, his avatar and the phone number.
According to the screenshots, the in-call features would include switching back to messaging session, call-muting and call direct through the speaker. During the VoIP session, switching to another application will place a colored bar at the top of the screen so that the user can switch back to the call through only a tap.
Another feature to note is the camera button on the keyboard’s top, tapping which attaches several photos to the text message. Users can send multiple photos in the current iOS app but it requires a few taps so this tweak is a welcome.
It was also introduced by WhatsApp co-founder Jan Koum at MWC that voice on WhatsApp would be introduced in Q2, 2014. He also mentioned that Android and iOS would get these features, while BlackBerry and Windows would come later.
The Guardian says VoIP between WhatsApp users would be free. The app currently has voice mail to send recorded messages.
WhatsApp is free to download and works on iOS 4.3 and above.
(via iPhoneItalia (Translated))