GitHub repositories like iptv-org host massive collections of publicly available IPTV links. These playlists often include Channel 4 and its sister channels (E4, More4, Film4).
There are several ways to access Channel 4 via M3U, ranging from community-maintained lists to custom-generated links. Download CHANNEL4 m3u
Once you have the M3U file or URL, you can play it on various devices: Download CHANNEL4 m3u