According to WABetaInfo, messaging service WhatsApp is currently testing multi-device support for voice and video calling. While rumours of the upcoming feature have been doing the rounds of the Internet for a while now, latest reports say WhatsApp is testing calls when the multi-device is configured for the same account, between difference devices. While there's no information about when the feature will be available officially, it's suggestive of how seriously the Facebook-owned company is working on multi-device support.