You could very quickly check whether you’re able to make this work by accessing ‘Guest Mode’, which was added several years later following the Chromecast’s initial launch. This allows the device to open up to guest access without that user needing to first establish a connection to your Wi-Fi network.?
This works by utilising a Wi-Fi beacon built into the Chromecast. Once an app that’s capable of streaming is opened on the guest’s device, it will search for the beacon in order to create a bridge. Once connected, they should be able to ‘Cast to Chromecast’ just as you would normally do across a network.
For this pairing to work, the Chromecast device will generate a random four-digit code that’s then emitted as an audio signal to nearby devices, although human ears won’t be able to pick this up. While quite nifty, this type of pairing is notoriously temperamental and won’t always work, so you might find you will need to pair using the code displayed on the TV or monitor.
You can also mirror the display of an Android device to a Chromecast streaming stick without using Wi-Fi.
To mirror an Android device, open the Chromecast app on it (the Chromecast app is now known as Google Home), tap on the burger menu in the top left corner (this looks like three lines together), tap on Cast Screen/Audio, and then choose your Chromecast device.
Screen mirroring works differently to wireless display (which has been part of Android since Jelly Bean 4.2, as the resultant output is less laggy and choppy than wireless display). Screen mirroring with Chromecast does, however, require Android KitKat 4.4.2 or later.
If your Chromecast is connected to a TV that is for whatever reason sat in a Wi-Fi blackspot, then you can (if you have a long enough Ethernet cable or powerline) connect the Chromecast directly to an Ethernet port of your router via an Ethernet adaptor for Chromecast.
This wired connection will create a fast and reliable link for the Chromecast device. All the user needs to do is to connect the included USB cable from the Ethernet adapter to the Chromecast, and then run an Ethernet cable from the router to the Ethernet adapter. The adapter itself will need to be plugged into an electrical socket as well. Once all this is done, the Chromecast device will automatically be set up to use an Ethernet connection instead of a Wi-Fi network.