MP4 vs WebM: Which Video Format You Get
The container matters more than the name. MP4 with H.264 plays almost everywhere; WebM is smaller and open but less universally supported, especially on older Apple devices.
MP4 (H.264/AAC)
The safest choice. It plays in Safari, QuickTime, Windows Media Player, Android and every editor. That is why DownloadTray prefers MP4 when the platform offers it.
WebM (VP8/VP9/Opus)
Common on YouTube and some TikTok audio streams. Browsers handle it well; older iPhones and some TVs do not. If a file will not open in Photos, the container is often the reason.
What DownloadTray does
It saves the container the platform serves. It does not re-encode MP4 to WebM or the reverse, because that would change the file and take time for no quality gain.
If a file will not play
Try VLC first. If it plays there, the file is fine and the player is the problem. Converting the container with an editor is the last step, not the first.
Frequently asked questions
Why did I get WebM instead of MP4?
The platform served that container for the stream. DownloadTray does not transcode.
Does MP4 mean better quality?
No. The container and the codec quality are different things; the file is what the platform serves.
What plays on iPhone?
MP4/H.264 reliably. WebM support is limited, so use VLC or convert the file.