A new app launched by Telstra allows calls to be made over a landline service while using a compatible mobile device instead of a standard home phone handset.
The telco has launched the Telstra T-Voice app for iOS and Android devices.
The free app is available for Telstra customers with ADSL or National Broadband Network services who also have a Telstra home phone service.
When installed, the app allows calls to be made using the mobile device at standard home phone rates while connected over their home's Wi-Fi.
T-Voice can be installed on up to seven devices. It can run on an iPhone, iPod Touch or iPad running iOS 6.1 or later as well as smartphones and tablets running Android 4.0 or later.
Telstra's T-Voice 502 home phone handset is also compatible with the service and offers high-definition sound over NBN-based connections.
The service also requires Telstra's T-Gateway (797) or Gateway Max router.
Contacts can be shared across devices.
Rival telco Optus earlier this year unveiled a Wi-Fi calling app for iPhones and Android smartphones.
Unlike T-Voice, Optus' WiFi Talk allows smartphone users to make calls at standard mobile rates while employing a Wi-Fi service rather than a cellular connection.
Vodafone Australia CEO Iñaki Berroeta said last month said that would launch "very soon" on his company's network, though Vodafone Wi-Fi calling is unlikely to be through a discrete app.