WHATSAPP has taken its latest swipe at mobile networks, having added a voice calling feature to its Android app.
All users of WhatsApp for Android can now make use of the app's free voice calling feature, which was rolled out to a handful of users last month and follows the launch of a voice messaging feature.
The updated version of the app is not yet showing up at Google Play, but can be downloaded directly from the WhatsApp website.
Of course, to make use of the voice-calling feature you'll need internet access on your mobile device, and Facebook-owned WhatsApp recommends an unlimited data plan if you can't stick to WiFi.
The firm also said that the feature will work on any smartphone running at least Android 2.1, but tablets aren't supported at this time.
The arrival of WhatsApp's voice-calling feature is good news for users of the app, but is likely to have mobile operators worried.
WhatsApp already makes text allowances redundant for many smartphone users, and the arrival of a voice-calling feature could make bundled minutes equally superfluous.
WhatsApp isn't the only company sounding the death knell for traditional mobile phone contracts, as the likes of Apple's iMessage, Facebook Messenger and Viber are also creating concerns for mobile networks.
Pamela Clark-Dickson, principal analyst for consumer services at Ovum, said: "Mobile operator fears regarding VoIP-led cannibalisation of voice revenue might be about to be realised, as WhatsApp begins the long-delayed process of officially adding a calling feature to its messaging app.
"Given that the popularity of WhatsApp for messaging has caused a decline in SMS traffic and revenues for a number of operators, it would be fair to assume a similar outcome for operator voice services, especially given that WhatsApp's user base is well on track to reach 1.1 billion in 2015."
Clark-Dickson added that, while other firms have long been causing concerns for networks in this area, WhatsApp is perhaps the most feared by operators given its popularity and easy-to-use features. This could see it one day becoming a mobile virtual network operator (MVNO).
"A key differentiator for WhatsApp has been its continued focus on providing easy-to-use, high-quality communications services," she said.
"The focus on ease of use seems to have been retained with WhatsApp Calls, with the company enabling one-tap calling of contacts via the app’s new Calls tab.
"The new Calls capability opens up the opportunity for Facebook to start generating revenues from WhatsApp, for example by offering add-on packages of minutes and/or messages to reach non-WhatsApp contacts. WhatsApp could also, conceivably, establish itself as an MVNO.
"In addition, WhatsApp is in a good position to add complementary features, such as video calling, which would strengthen its communications proposition."
As if to incite further fear in mobile operators, WhatsApp has said that the voice-calling feature will arrive on iPhones in the coming weeks.
There's no word yet on a launch for BlackBerry or Windows Phone devices. µ
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