How it works
Google Cast and AirPlay connect supported sending apps or devices with compatible receivers. A media app may hand playback to the receiver, while screen mirroring reproduces the sender’s display. These are distinct modes with different behaviour when the phone is locked, another app opens or playback control changes.
Important differences and limits
Compatibility depends on the app, receiver, operating system and network arrangement. Being on the same named Wi-Fi does not guarantee that device discovery is allowed: guest isolation or network segmentation can block it. Some media apps restrict casting or mirroring, and supported audio or video formats can differ.
A useful practical check
Confirm the exact method offered by the app and receiver. Check that both are on the appropriate local network and have current supported software. Test discovery, playback, sound and reconnection after sleep. If a receiver is absent, investigate network discovery before assuming a faster internet subscription is required.
An example in practice
For example, casting a supported film from its app can differ from mirroring a presentation containing notifications. For a presentation, verify which information appears on the shared screen and silence unwanted alerts. Test the actual content beforehand, including sound and any protected video, instead of relying on successful playback of an unrelated clip.