How To Use AllShare Cast On Samsung Galaxy S3 - P^i You can connect your Samsung Galaxy S3 to a large screen by using an AllShare Cast dongle, and then share your contents. This feature may be unavailable depending on your region or service provider. Some files may be buffered while playing depending on the network connection. To save energy, deactivate the AllShare Cast feature when not in use. If you specify a Wi-Fi frequency band, AllShare Cast dongles may not be found or connected.