While the WhatsApp voice calling feature has been available for Android, iOS and BlackBerry OS users for quite some time, Windows Phone has been without the VoIP feature. But it seems the wait is over as WM Power User (WMPU) has revealed that the feature has been finally made available on the WhatsApp beta edition for Windows Phone users. 

The WhatApp voice calling feature is still not available on the final version of the app, but it is exclusively available on its beta version. Windows Phone users who belong to the WhatsApp beta testing program can take advantage of it, reports Ubergizmo

According to WM Power User, when a user makes a VoIP call with the latest WhatsApp beta app with version 2.12.40, he will be able to see an interface that appears similar to the general voice calling interface of Windows Phone. The publication claims that its testers have already tested the VoIP feature. It states that voice calls made on high bandwidth connection is of excellent quality.

The WMPU post, which was published in April, says the WhatsApp support team had confirmed that the developers were working on the WhatsApp calling feature for Windows Phone users. However, the support team wouldn't comment on release timelines.

For Android OS, the voice calling feature was first launched on an invitation-only basis. However, the feature later was made available to all users.

As of this writing, there is no official confirmation from WhatsApp on when non-beta testers will be able to access the VoIP calling feature. Ubergizmo claims the service is already available on beta edition and will arrive soon for general users. Even though there are several well-known VoIP calling apps, such as Skype, Line, Viber and Facebook Messenger, WhatsApp is the most popular, with more than 800 million users.