If you have a modern Android phone, it's very likely that your carrier already supports it. VoLTE and VoWiFi callsAlthough you may not be using them yet, these two technologies are designed to improve voice quality, reduce dropouts, and make better use of both your 4G network and your home or office Wi-Fi.
In Spain, operators such as Movistar, O2, Vodafone, Orange, Digi and many others These features have been expanding, especially now that 3G is being phased out. The aim of this guide is to help you understand exactly what VoLTE and VoWiFi are, what advantages they offer, which carriers they work with, how to activate them on Android (and also on iPhone, for reference), and what more advanced options exist to enable them even on non-certified phones.
What are VoLTE and VoWiFi and why do they matter?
In a typical call, the mobile phone uses a voice channel independent of the data channelBecause of this, when you're on 4G and you receive or make a call, the phone usually automatically drops to 3G (or even 2G) to complete it, with the consequent impact on quality, connection times, and even battery consumption.
With VoLTE (Voice over LTE)The mobile phone uses the 4G network to send voice as data, without having to "step back" to 3G. Calls use the same infrastructure as browsing, but are managed with priority and quality of service so that the voice sounds clear and stable.
For its part, VoWiFi (Voice over WiFi) It allows calls to be routed through any compatible Wi-Fi connection, as if the router were another antenna from the operator. This is especially useful indoors with poor mobile coverage: basements, ground floors, buildings with a lot of metal structure, or rural areas where the signal barely reaches.
Both technologies remain normal calls from your mobile numberThey are not apps like WhatsApp or Skype: you don't need the other person to have anything installed or be connected to WiFi, and they are billed as voice calls on your plan.
Differences between VoIP, VoLTE and VoWiFi
Sometimes everything gets lumped together, but it's helpful to separate concepts to have clarity. One Generic VoIP call It is any voice call that travels over the data channel, whether WiFi or mobile data, usually using third-party applications (WhatsApp, Skype, Viber, etc.).
Within that large group of VoIP calls, the following are included: VoLTE and VoWiFi These technologies are managed by the mobile operator itself, integrated into the network and the system's phone app, without any extra apps or additional accounts. Technically, they are still Voice over IP, but with quality guarantees, traffic prioritization, and full integration with your phone number.
When you're using VoWiFi, your mobile phone uses the wireless network you are connected to as if it were part of the operator's infrastructure. With VoLTE it does something similar, but relying on the 4G/LTE network and simultaneously maintaining data at maximum speed.
The key advantage over VoIP apps like WhatsApp is that You don't change your interface or number.You call from your usual dialer, to any landline or mobile, and the call is charged as a regular call on your plan. Furthermore, the operator can guarantee a much higher level of quality when network coverage or Wi-Fi is adequate.
Operators with VoLTE and VoWiFi in Spain
In the Spanish market, more and more companies have been adding support for these technologies, especially as 3G is phased out and the focus shifts to 4G and 5G. List of operators with VoLTE It's quite extensive.
Currently, VoLTE is offered by brands such as Movistar, O2, Vodafone, Lowi, Orange, Jazztel, Simyo, Yoigo, MásMóvil, Pepephone, Digi and FinetworkThere are also smaller mobile virtual network operators (Wifitech, Xenet, tumovil, Lemmon, among others) that support it, although in these cases it usually depends on the wholesale network they are operating on in each area.
As for the VoWiFiThe list is somewhat shorter. They have this feature active, primarily for contract lines, by operators such as Movistar, O2, Vodafone, Orange, Jazztel, Simyo and DigiSeveral brands disappear from the VoLTE list here, so it's advisable to check your company's specific terms and conditions.
In some smaller MVNOs, the availability of VoWiFi and VoLTE may change depending on whether they are currently using Movistar, Orange, Vodafone or other network coverageIt's possible that VoLTE might work under one network footprint but not another, so if you're using an MVNO, it's a good idea to test it in different locations or consult their support.
Advantages of using VoLTE and VoWiFi
Adopting these technologies has a number of advantages over traditional 2G/3G phone calls. The most obvious is the improved sound qualityThe voice is transmitted using high-definition codecs (HD Voice), with more bandwidth and less compression, making it sound clearer, with less background noise and a greater sense of "being right next to" the speaker.
Another key point is the speed in call setupWith VoLTE, the ringtone is practically instantaneous, without that slight delay typical of when the phone switches from 4G to 3G to dial. This is especially noticeable when you make many calls in a row or when you're used to 2G/3G speeds.
VoWiFi calls shine especially in areas with poor mobile coverageThey allow you to make and receive calls when, under normal circumstances, you would barely have a signal. All you need is a stable Wi-Fi network, without micro-disconnections, and with reasonable bandwidth.
There are also less visible, but very interesting, advantages. For example, with VoLTE the phone doesn't have to constantly switch network technologies, which helps to slightly reduce battery consumption compared to calls over 2G/3G. Plus, you can continue browsing, using apps, or downloading files at full speed while you're on a call.
Finally, VoWiFi contributes to offload some of the mobile network trafficThis is because some calls are routed through users' Wi-Fi networks. In the long run, this benefits both you and the other customers of the operator, especially in areas where the mobile network is under heavy load.
How to activate VoLTE on Android phones
The exact steps to activate VoLTE may vary slightly depending on your phone's custom interface (Samsung One UI, Xiaomi MIUI, Pixel, etc.), but the general structure of the settings is usually very similar. First, make sure you have your phone. updated with the latest system version available and that network selection is in automatic mode (5G/4G/3G/2G).
On most modern Android phones, you can follow a path similar to this: go into Settings > Network & Internet (or “Connections”) and then under “Mobile network” or “Mobile networks”. There you should find a section for preferred network type, where it is recommended to choose 5G/4G/3G/2G (automatic connection) so that VoLTE works correctly when it is available.
On many mobile phones you will see a switch with names like “4G Calls”, “VoLTE Calls” or “Enable VoLTE”Simply activate this feature so your phone will attempt to make calls over 4G whenever the network allows it. On Android 10 or later, this option is usually found within "Preferred network type" or in an advanced section of the network menu.
If you can't find it easily, you can use the search function built into the system settings by typing terms like “VoLTE”, “4G Calls” or “LTE Calls”Some manufacturers move the option from one menu to another, but it is almost always locatable using the search bar.
In Android 9, the menu structure may be slightly different: sometimes the setting is within Settings > Networks & Internet > Mobile Network > Advancedwhere you'll see the selection of “4G or higher” and the switch to activate VoLTE, if your carrier has enabled it for that model.
How to activate VoWiFi on Android phones
In the case of VoWiFi, the scheme is similar but focused on the WiFi callsFirst of all, make sure your mobile phone is compatible (you can use lists published by operators like Vodafone or Orange) and that your plan has the service activated, as some companies limit it to contract lines.
On many Android phones the typical path is: go to Settings > Networks & Internet > Calls & SMS (or a similar menu) and there you should see an option called “WiFi Calling” or “WiFi Calling”. By activating it, your phone will start using the available Wi-Fi connection when mobile coverage is poor or nonexistent.
In other layers, such as Samsung's, the most common path is Settings > Connections > Wi-Fi CallingIt is also common to find a direct "Wi-Fi Calling" icon in the quick settings bar that slides down from the top of the screen.
Another possibility is to enter the system's phone application, go to the menu of Settings > Calls and from there activate “Wi-Fi Calling”. The name may vary slightly depending on the brand, but it usually includes the words “Wi-Fi” or “Wi-Fi” along with “Calls”.
Keep in mind that when VoWiFi is active, the phone gives prioritize WiFi network over mobile coverageIf your Wi-Fi connection is unstable (intermittent outages, low bandwidth, network congestion), you might experience audio problems or even dropped calls. That's why many carriers recommend using it, especially when mobile coverage is very poor.
