This free option significantly improves the quality of smartphone calls, but few people know about it!

Tired of those inaudible phone conversations with mediocre, muffled, and garbled sounds? Simply activate a free option included in your package to enjoy high sound quality...

For several years now, telecom operators have been offering an option that lets you enjoy high-definition quality sound for your conversations. Say goodbye to static and other distracting noises. To achieve this, they rely on two well-proven techniques: VoLTE and VoWifi. Behind these acronyms lie two channels through which voice transits.

• The first, VoLTE (for Voice over LTE), is none other than the 4G network deployed by operators. Cell phone calls therefore do not use the traditional 2G or 3G network.
• The second, VoWifi, applies the same principle, but this time calls are made via the Wifi network to which the mobile is connected, at home or in a hotel or restaurant, for example.

In both cases, the voice is transformed on the fly into data packets for transmission via the Internet.

Both VoLTE and VoWifi have their advantages. Firstly, the audio quality of calls is far superior to those made over the standard network. Sound is clear and uninterrupted, whether using the smartphone's speaker and microphone or a wired or wireless headset. Secondly, making a VoLTE or VoWIfi call does not deprive you of an Internet connection during the conversation, unlike conventional calls. So you can search for information on the web using your smartphone while remaining in communication with your correspondent, which is rather practical.

The good news is that VoLTE and VoWifi don't need to be paid for. If your mobile package includes a data envelope for an Internet connection, chances are you'll be able to enjoy HD phone calls at no extra cost. All you need to do is check that your operator has activated this option in your personal space. 

Note that passing these calls using VoLTE or VoWifi does not eat into your mobile data rate. They are counted as ordinary calls. Next, you'll need a compatible smartphone with 4G or WiFi coverage. The vast majority of today's mobiles are. Finally, you'll need to check that the option is activated in your mobile's settings. And to make sure that calls do indeed go through VoLTE, nothing could be simpler. Switch off WiFi on your mobile and launch a call. If the 4G or LTE icon is still displayed, you're on.

To take full advantage of high-definition voice during a call, your correspondent must also have VoLTE or VoWifi. Otherwise, the sound automatically adjusts to the lowest quality. What's more, should you lose your connection to the 4G network during a conversation, the call will not be interrupted. The phone will automatically switch back to the 2G or 3G network without interruption, returning to normal quality. And you'll notice the difference in quality immediately!