Deutsche Telekom has become the latest European operator to launch Wi-Fi calling as part of efforts to enable users to make calls where cellular network coverage is poor or non-existent.
The operator has now rolled out the service in Germany under WLAN Call, noting that it is an add-on with no monthly charge. The move comes after Deutsche Telekom trialled the technology at the CeBIT 2016 trade fair together with Samsung. It already offers voice over LTE (VoLTE) services in Germany.
"Customers simply need a WLAN Call-enabled smartphone and a VoLTE-enabled mobile contract," the company said. It noted that calls would be handed off from the VoLTE to the Wi-Fi network "without interruption when there is sufficient signal strength."
Wi-Fi calling was a major theme of 2015 with a number of launches across Europe. In the UK, for example, both EE and Vodafone UK launched Wi-Fi calling last year. Like Deutsche Telekom, the operators took the approach of embedding the service in the smartphone so it can be accessed via the normal phone dialler.
This contrasts with the apps-based strategy of rivals Three UK, which offers VoWi-Fi via the Three InTouch app, and O2 UK, which uses the TU Go app.
A lack of compatible devices has hampered the services somewhat, however.
In Germany, only two devices are enabled from the start: the Samsung Galaxy S6 and Galaxy S6 edge. Deutsche Telekom said more smartphones would follow over the next few months.
Other operators within the Deutsche Telekom group also now offer VoLTE of Wi-Fi calling services. T-Mobile Czech Republic offers both, for example.
However, T-Mobile Poland recently said the lack of compatible and affordable devices was proving to be an obstacle to its ambitions to offer both services on a commercial basis. The company is carrying out tests in the meantime.
- see this Deutsche Telekom release
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