US-based telecommunication services provider Sprint is reportedly developing a new technology which will allow WiFi calling through Android devices.

The new technology is expected to be compatible with devices running on Android 4.2 and above versions, while it is expected to be primarily available on two of its devices.

According to the sources, the WiFi calling service needs software update but incurs no monthly fee.

Sprint is expected to launch the service on its current devices through maintenance updates, while it would come as a default option for new devices.

The calls offered through the service are not interchangeable with calls made over CDMA and the calls can’t be shifted between two Wi-Fi systems.

The service is expected to be available only in the US and needs the device’s Android Location Services to be turned on to make Wifi calls.

Wi-Fi Calling will not be supported from other locations, while using a VPN and the outbound Wi-Fi calls can not be done without a CDMA signal.