Why won't my TV appear in the list?

Screen mirroring finds your television using mDNS, the same zero-configuration mechanism that makes printers and speakers appear without you typing an address. It works by broadcasting a small message to everything on the local network and listening for replies. Anything that stops that broadcast stops discovery, and networks stop it for several ordinary reasons.

Work through these in order. The first one accounts for most cases.

1. Both devices on the same network

More specifically, the same network, not merely the same router.

• Mobile data. If the iPhone has dropped to cellular, it is not on your Wi-Fi at all. Check the Wi-Fi symbol.
• Guest networks. A guest network is a separate network by design. Both devices must be on the main one.
• Split bands. Many routers broadcast 2.4 GHz and 5 GHz under different names, for example Home and Home_5G. Those are two networks. A television on one and a phone on the other cannot see each other.
• Mesh systems. Usually fine, since they present one network, but a poorly configured mesh can isolate a node.

2. Client isolation on the router

This is the setting that catches people who have checked everything else. It goes by several names (AP isolation, client isolation, station isolation, guest mode, wireless isolation), and it does exactly what it says: it prevents devices on the network from communicating with one another. Each device can reach the internet, but nothing else on the network.

It is on by default on a lot of hotel, campus, office and apartment-building networks, and occasionally on consumer routers.

Look for it in your router’s admin page under Wireless, Advanced Wireless, or Guest Network. Switching it off fixes discovery immediately.

If it is not your router (a hotel, a university, a workplace), you cannot fix it, and no app can. That network is designed to prevent precisely this.

3. Multicast or mDNS filtering

Some routers, and most enterprise networks, filter multicast traffic to reduce noise. Since mDNS is multicast, filtering it makes discovery impossible even with isolation switched off.

Settings to look for: IGMP snooping, multicast filtering, mDNS reflector or Bonjour gateway. Enabling an mDNS reflector on a network that has one, or disabling multicast filtering, resolves it.

4. The receiver app is not actually open

The receiver on the television has to be running and on screen. It is not a background service and it does not wake on demand. If the television went to a screensaver or a different app took over, go back to it.

5. VPN on the iPhone

A VPN can route local traffic through the tunnel, which prevents the phone from seeing anything on your own network. Switch it off and try again.

6. iOS local network permission

The first time it runs, the iPhone app asks for permission to find devices on your local network. If that was declined, discovery cannot work. Check Settings → Vistacast → Local Network and turn it on.

Still nothing?

Two quick tests that narrow it down fast:

Test the network, not the app. On the iPhone, try to reach any other device on your network: a printer, a smart speaker, a NAS. If nothing local is reachable, the problem is the network and you have your answer.

Test with a phone hotspot. Put the television and the iPhone both on a hotspot from a second phone. Hotspots do not isolate clients. If discovery works there, your usual network is the cause.

If neither helps, write to us with the make of your router and your television, and a person will look at it.