Public Wi-Fi: the danger you don't see. And why 5G is safer.

You're waiting for your train, you open your laptop, and there it is: Free WiFi — connect. One tap and you're online. Convenient, free, and at first glance harmless.

That very convenience is the problem. Because an open, public Wi-Fi network is one of the easiest places for someone to watch what you're doing. Not in theory — in practice, with tools that are freely downloadable.

What really happens on an open network

A public Wi-Fi network is a shared space. Everyone connected is, in a sense, in the same room. And an attacker needs only a few techniques:

• Eavesdropping (sniffing). Traffic that isn't properly encrypted can literally be plucked out of the air. Passwords, cookies, sessions — readable to anyone listening.
• The evil twin. An attacker sets up their own hotspot with a trusted name — "Station_Free_WiFi", "Hotel Guest". Your device connects automatically, and all your traffic runs through the attacker.
• Man-in-the-middle. The attacker positions themselves between you and the website. You think you're talking to your bank; in reality you're talking to them, and they're talking to your bank.

The treacherous thing about public Wi-Fi isn't that it goes spectacularly wrong. It's that everything just seems to work — while someone reads along.

"But there's a padlock, isn't there?"

Fair point: HTTPS (the padlock in your browser) encrypts the connection to a website, and that helps enormously. But it's not a complete shield.

• Not everything runs over HTTPS — apps, background processes and older services sometimes still leak data.
• With an evil twin or man-in-the-middle, an attacker can lead you to a fake page, or try to fool you with false certificate warnings.
• Metadata — which sites you visit, when, how often — remains visible, even with HTTPS.

HTTPS is a good front door. But on public Wi-Fi you're still leaving the windows ajar.

Why your 5G connection is fundamentally safer

When you work with your smartphone — via 4G or 5G — the picture looks very different. The mobile network isn't an open, shared space, but a closed network with built-in security.

• Encryption by design. The traffic between your device and the mast is encrypted at network level, regardless of which app or site you use.
• No "strangers in the same room". Every device has its own authenticated connection to the network via the SIM card. You're not simply on the same segment as a stranger.
• No evil twins. Imitating a mobile mast is exponentially harder than setting up a Wi-Fi hotspot with a trusted name. 5G also added extra protection against precisely that kind of attack.
• You're the only user of your connection. Where public Wi-Fi is shared by dozens of strangers, your mobile data connection is yours alone.

The rule of thumb is simple: sensitive matters — banking, work email, logging in — are better done over your mobile data than over free Wi-Fi. And if you do use public Wi-Fi, put a VPN over it.

The catch: indoors, 5G often drops out

And here's the sting — and immediately the reason why, as an indoor specialist, this subject is close to our heart.

The safest choice is your 5G connection. But precisely in the places where people flock to public Wi-Fi — stations, airports, hotels, offices, underground floors, large concrete buildings — the mobile signal indoors is often weak or non-existent. The result is predictable: people give up and tap "Free WiFi", precisely because the safer alternative isn't there.

In other words: poor indoor 5G coverage pushes people towards the less secure network. Good indoor mobile coverage does the opposite — it makes the safe choice the easy choice too.

For businesses, hotels, hospitals and apartment buildings, that's no detail. Reliable 5G indoors means your staff, guests and residents handle their sensitive matters over a secure network, rather than over a shared Wi-Fi that no one controls.

In short

• Public Wi-Fi is convenient, but structurally insecure: sniffing, evil twins and man-in-the-middle are reality, not science fiction.
• HTTPS helps, but doesn't cover everything.
• Your 5G connection is, by design, the safer choice for anything sensitive.
• But that only works if you have 5G coverage indoors too — and that's often where it falls short.

The best security is the kind you don't have to force. Make sure the safe connection is available everywhere, and no one needs to fall back on free Wi-Fi.

Unsure about the 5G coverage in your building, hotel or office? Request a free coverage analysis — we'll simply measure it for you, with no obligation.