No, you cannot see what someone is doing on their phone through wifi in the sense of reading their messages, viewing their screen, or tracking their app activity. Sharing a Wi-Fi network only lets you see that a device is connected, not what the person is typing, watching, or browsing on that device.
What a network administrator can actually see
If you control the router, you can see a list of connected devices, their IP addresses, and the domain names they visit. For example, you might see that a phone on your network is connecting to Netflix.com or Facebook.com. But that is where the visibility stops. You cannot see which specific videos were watched, which posts were viewed, or what messages were sent. This is because modern web traffic is encrypted with HTTPS, which scrambles the actual content of the data traveling between the phone and the website. The router only sees the destination address of the data packets, not what is inside them. So while a network administrator can build a rough picture of which sites someone visits, they cannot see the details of what the person does on those sites.
How modern phones protect your privacy on wifi
Modern mobile operating systems include MAC address randomization, which prevents tracking by using a unique, randomized MAC address for each Wi-Fi network. This means that even if someone is monitoring the network, they cannot identify your specific device across different networks or track your movements. Beyond that, phones have built-in security features like app sandboxing and data encryption. App sandboxing ensures that each app operates in its own isolated environment, so one app cannot access another app's data. Data encryption means that even if someone intercepts the data traveling to and from your phone, they cannot read it without the encryption key. These protections make remote spying through Wi-Fi extremely difficult for the average person.
Can someone hack your phone through wifi?
Theoretically, yes, but the risks are far lower than most people fear. A skilled attacker could attempt a Man-in-the-Middle attack, where they intercept communication between your phone and the network, or set up a rogue access point that mimics a legitimate network to capture your data. However, these attacks require advanced technical knowledge, specialized tools, and a specific target. Average users are unlikely to be targeted because the effort and skill required are high, and the legal consequences are severe. Modern phones also have built-in protections that make these attacks harder to execute successfully. For most people, the chance of being hacked simply by connecting to a Wi-Fi network is very low, especially if the network is secured and the phone's software is up to date.
How to protect your phone from wifi attacks
You can take practical steps to reduce your risk. Use WPA2 encryption on your home router and set a strong password to prevent unauthorized access to your network. On public networks, use a VPN to encrypt your traffic, which makes it much harder for anyone to intercept or read your data. Keep your phone's operating system and apps updated, because updates often include security patches that fix known vulnerabilities. Avoid connecting to suspicious or unsecured networks, especially ones that do not require a password. Enable two-factor authentication on your important accounts, so even if someone steals your login credentials, they cannot easily access your accounts. These measures do not require technical expertise, but they significantly reduce your exposure to Wi-Fi-based threats.
When spyware changes the rules
If someone wants to see what you are doing on your phone, they cannot do it just by sharing your Wi-Fi network. To actually monitor your screen, messages, or app activity, they would need to install spyware directly on your device. This requires physical access to your phone or tricking you into installing a malicious app. A suspicious partner or employer would need to unlock your phone, disable security settings, and install monitoring software, or convince you to download an app that secretly records your activity. This is device-level spyware, not network-level monitoring. Sharing a Wi-Fi network alone does not give anyone that kind of access. So if you are worried about someone spying on you, the real question is whether they have had physical access to your phone, not whether they are on the same network. If you suspect this has happened, learning how to monitor another phone for free can help you recognize the warning signs of common spyware tools.
