{"id":48042,"date":"2026-09-03T00:29:26","date_gmt":"2026-09-03T00:29:26","guid":{"rendered":"https:\/\/noticiatecnologia.com\/como-usar-wifi-publico-com-seguranca\/"},"modified":"2026-09-03T02:13:59","modified_gmt":"2026-09-03T02:13:59","slug":"how-to-use-public-wi-fi-safely","status":"publish","type":"post","link":"https:\/\/noticiatecnologia.com\/en\/como-usar-wifi-publico-com-seguranca\/","title":{"rendered":"How to use public Wi-Fi safely on your mobile phone."},"content":{"rendered":"

You're at the airport, your flight is delayed, and the open network in the terminal is the only way to let people know when you're home, pay a bill, and check your work email. The connection works, but a question remains: who else is on this network, and what can they see about what you're doing? The answer is that a public network is shared, and what separates your traffic from that of a stranger are layers of protection that you yourself choose to activate.<\/p>\n

The good news is that these layers already exist on your phone and in two free apps. HTTPS, that padlock in the browser bar, protects the content of almost everything you open. Proton VPN creates an encrypted tunnel between your phone and the internet, so the caf\u00e9 network only sees a scrambled flow. 1.1.1.1 + WARP protects DNS queries and encrypts traffic, keeping the country visible without affecting the behavior of surrounding apps. With the right Android settings, the public network becomes a safe place for everyday tasks.<\/p>\n

This guide explains what happens when you join an open network, shows you how to use each app step-by-step, teaches you how to recognize fake networks with similar names, lists the Android settings that close the doors, and ends with a complete roadmap for the most common scenario: sitting in a caf\u00e9, connecting, and working in peace.<\/p>\n

What happens when you enter an open network?<\/h2>\n

On a network without a password, the signal between the cell phone and the router travels without encryption. Anyone on the same network, with the right equipment, can see the names of the websites you access and, in the case of pages without HTTPS, the content of what you send and receive. On networks with a shared password, like the one in a caf\u00e9, the situation is similar: the password is the same for everyone, and customer traffic passes through the same router, which belongs to the establishment.<\/p>\n

What protects you most of the time is HTTPS. When the website displays the padlock, the page content, the password you type, and the card details travel encrypted between the browser and the server. The network sees that you opened the bank's website, but it doesn't see what you did there. Banking apps, messaging apps, and online stores use the same type of encryption internally, even without displaying the padlock.<\/p>\n

Three points remain exposed: DNS queries, which reveal which domains you are searching for; traffic from older apps and websites that no longer use HTTPS; and the router itself, which may be misconfigured or in the hands of someone who has set up a fake network. VPN and protected DNS address exactly these three points.<\/p>\n

Proton VPN: Encrypted tunnel with a basic plan and unlimited data.<\/h2>\n

Proton VPN creates a tunnel between your mobile phone and a company server. Everything that leaves your device passes through this tunnel encrypted, and the internet caf\u00e9 network only sees a formless data stream going to a single address. Websites, in turn, see the Proton VPN server, not the network you are on. The basic plan is free, with unlimited data and no activity logs, making it the option for those who want to call and forget.<\/p>\n

\"Proton

Proton VPN: Fast and secure<\/h3> Android<\/span> <\/div> <\/div>
<\/span> 4,8<\/span>(1.3 million reviews)<\/span><\/div>
<\/svg><\/span> 100 million+ downloads<\/span><\/div><\/div> <\/svg><\/span> View on Google Play<\/span> <\/svg><\/span><\/a> <\/div><\/div>

The main screen has a large quick connect button, which automatically selects the server, and a list of countries for those who want to choose which country to use. For use on public Wi-Fi, the quick connect is sufficient. In the settings, there is an emergency lock, called a kill switch: if the tunnel drops, the phone will lose internet access until the VPN is restored, instead of continuing to browse without protection.<\/p>\n

    \n
  1. Install Proton VPN from the Google Play Store and open the app.<\/li>\n
  2. Create an account with an email address or sign in with an existing account. The basic plan becomes available immediately after registration.<\/li>\n
  3. Tap the quick connect button. Android will ask for permission to create a VPN connection; accept.<\/li>\n
  4. A key icon appears in the status bar. From there, all mobile traffic passes through the tunnel.<\/li>\n
  5. In Settings<\/b>, Turn on the kill switch so that a tunnel outage doesn't leave you browsing unprotected.<\/li>\n
  6. Also enable the option to connect automatically when starting your phone, if you want the protection turned on all the time.<\/li>\n<\/ol>\n

    What to expect: With the VPN enabled, the speed drops slightly because the traffic is diverted to the server. On slow public networks, this is noticeable in video; in browsing and messaging, it's almost imperceptible. On the basic plan, the app chooses the server from those available for that plan, and location-dependent websites may show a different country until you turn off the VPN.<\/p>\n

    An important detail: some public network login portals don't open with a VPN enabled. Connect to the network, log in to the establishment's page, and only then turn on Proton VPN. After that, leave the tunnel active until you leave the network.<\/p>\n

    1.1.1.1 + WARP: Protected DNS and encrypted traffic without changing countries.<\/h2>\n

    Cloudflare's 1.1.1.1 + WARP tackles the problem from a different angle. In 1.1.1.1 mode, it replaces the network's DNS with Cloudflare's encrypted DNS: queries that reveal the domains you access are no longer visible to the router. In WARP mode, it also encrypts the traffic between your mobile phone and the Cloudflare network, without changing the apparent country: websites continue to see you as being in Brazil, banking and delivery apps continue to work as always, and the coffee shop's network stops seeing what passes through it.<\/p>\n

    \"1.1.1.1

    1.1.1.1 + WARP<\/h3> Android<\/span> <\/div> <\/div>
    <\/span> 4,1<\/span>(1.4 million reviews)<\/span><\/div>
    <\/svg><\/span> 100 million+ downloads<\/span><\/div><\/div> <\/svg><\/span> View on Google Play<\/span> <\/svg><\/span><\/a> <\/div><\/div>

    The interface is a single button. You turn it on, a key icon appears in the status bar, and that's it. There's no account to create or server to choose. In the settings, a menu allows you to switch between "1.1.1.1" mode, which protects only DNS, and "WARP" mode, which protects both DNS and traffic. For public Wi-Fi, use WARP.<\/p>\n

      \n
    1. Install 1.1.1.1 + WARP and open the app.<\/li>\n
    2. Accept the terms upon first opening.<\/li>\n
    3. Tap the center switch. Android will ask for permission to set up a VPN connection; accept. This is how the app is able to redirect traffic.<\/li>\n
    4. Open the settings menu and check if the active mode is WARP. If it's set to 1.1.1.1, change it.<\/li>\n
    5. Use the internet normally. To pause, tap the switch again.<\/li>\n<\/ol>\n

      What to expect: WARP is lightweight and barely affects speed, and by keeping the country visible it doesn't interfere with services that depend on your location. It protects the path between your phone and Cloudflare; from there, traffic goes to websites via the normal internet, which is already sufficient protection against those on the same network. Just like with a VPN, log in to the captive portal before turning it on.<\/p>\n

      The two apps should not be running at the same time. Android only allows one VPN connection to be active at a time; when the second one is turned on, the first one is turned off. Choose one for each situation: Proton VPN when you want to hide the originating network and choose the exit country; 1.1.1.1 + WARP when you want light protection without changing the apparent country.<\/p>\n

      Fake network with a similar name: how to recognize the scam<\/h2>\n

      The most common scam in busy places is the fake network: someone creates an access point with a name almost identical to the establishment's, such as "Cafe_Wifi_Free" next to "Cafe Wifi," and waits for people to connect. All traffic passes through the scammer's equipment, who can set up fake login pages asking for email, password, or credit card information.<\/p>\n

      Recognizing the correct network is a matter of attention. Ask at the counter for the exact name of the network and compare it letter by letter. Be wary of names with "free," "gratis," or "premium" that the sign doesn't mention, of open networks next to password-protected networks in the same place, and of login portals that ask for email passwords, card details, or app downloads. No establishment needs this information to provide Wi-Fi access.<\/p>\n

      If you've already connected and noticed the error, turn off Wi-Fi, forget the network in your Android settings, and change the password for any service you logged into through the fake page. With VPN or WARP enabled, the scammer on the fake network only sees the tunnel, which greatly reduces the damage; but the fake login page remains a risk because you are the one entering the data on it.<\/p>\n

      Android settings that close the doors<\/h2>\n

      In addition to apps, Android itself offers options that reduce exposure on public networks. The first is automatic connection: in Settings > Network and Internet > Internet<\/b>, Tap the public network gear icon and turn it off. Connect automatically<\/b>. Therefore, the cell phone won't go back inside on its own the next time you walk through the door.<\/p>\n

      The second is the random MAC address. In the same network settings, in Privacy<\/b>, Keep the random MAC address option enabled. Each network will then see a different identifier for your device, making it harder to track you between locations. The third option is to forget the network when you leave: hold down the network name in the list and tap on it. To forget<\/b>. A short list of saved networks is a short list of names that someone can imitate.<\/p>\n

      Finally, check your sharing settings. Turn off file sharing via proximity and Bluetooth if you're not using them, and don't enable your phone's hotspot on a public network. Keep your system and apps updated; security patches close vulnerabilities that poorly configured networks exploit.<\/p>\n

      Tasks for the public school system and tasks to leave at home.<\/h2>\n

      With HTTPS, VPN, or WARP and the above settings, browsing, replying to messages, viewing email, watching videos, and using your bank's app are all secure tasks on a public network. The bank's app uses its own encryption, and the VPN adds a layer on top of it. What requires caution is different: typing passwords on pages without a security padlock, logging into suspicious websites, and installing apps suggested by the network.<\/p>\n

      Two tasks are better suited to a home network: the initial setup of a new service, where you create passwords and confirm personal data; and large downloads, which are demanding for everyone on the shared network and can be interrupted when the network goes down. Neither of these is prohibited on a public network, they just perform less efficiently.<\/p>\n

      Proton VPN or 1.1.1.1 + WARP: a direct comparison<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
      Criterion<\/th>\nProton VPN<\/th>\n1.1.1.1 + WARP<\/th>\n<\/tr>\n<\/thead>\n
      What protects<\/td>\nAll traffic is tunneled to the VPN server.<\/td>\nDNS (1.1.1.1 mode) or DNS and traffic to Cloudflare (WARP mode)<\/td>\n<\/tr>\n
      apparent country<\/td>\nThe server chosen by the app or by you.<\/td>\nThe same one you're in.<\/td>\n<\/tr>\n
      Account<\/td>\nRegister with email<\/td>\nNo account<\/td>\n<\/tr>\n
      Data limit<\/td>\nNo limit on the basic plan.<\/td>\nNo limits in WARP mode.<\/td>\n<\/tr>\n
      Activity logs<\/td>\nNo records.<\/td>\nProtects DNS against the local network.<\/td>\n<\/tr>\n
      Impact on speed<\/td>\nSmall, bigger in video<\/td>\nAlmost none<\/td>\n<\/tr>\n
      Best for<\/td>\nHide the source network and choose the departure country.<\/td>\nLightweight protection with location-based apps working.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

      Step by step: sit in the caf\u00e9, connect, and work in peace.<\/h2>\n

      This is the complete script for the most common scenario: you walk into a caf\u00e9, you need to work on your phone for an hour, and you want to do it without exposing anything.<\/p>\n

        \n
      1. Before leaving home, install Proton VPN or 1.1.1.1 + WARP and perform the initial setup on your own network.<\/li>\n
      2. At the caf\u00e9, ask at the counter for the exact name of the chain and the password, or read the sign.<\/li>\n
      3. Open the list of Android networks and compare the names letter by letter. Ignore networks with similar names that the poster doesn't mention.<\/li>\n
      4. Connect. If the "Log in to network" notification appears, open the establishment's portal and complete the process. Do not enter your email password or card details on this portal.<\/li>\n
      5. As soon as the internet connection is available, turn on Proton VPN via the quick connection or 1.1.1.1 + WARP using the switch. Check the key icon in the status bar.<\/li>\n
      6. Open a website with a padlock icon to confirm that everything is working.<\/li>\n
      7. In network settings, turn off Connect automatically<\/b> and check if random MAC addressing is enabled.<\/li>\n
      8. Work: email, messages, documents, banking app. Everything goes through the tunnel.<\/li>\n
      9. If the tunnel goes down, Proton VPN's kill switch cuts off the internet. Reconnect the VPN before continuing.<\/li>\n
      10. Leave system updates and large downloads to your home network.<\/li>\n
      11. When finished, turn off the VPN, turn off Wi-Fi, and forget the network if you don't intend to return.<\/li>\n
      12. At home, if any website asks for something other than your email or phone number, change the password for that service.<\/li>\n<\/ol>\n

        Common mistakes<\/h2>\n