M4S2MP4

M4S Converter focuses on one high-intent job: fixing a video.m4s file that has no sound, or turning separated audio.m4s and video.m4s fragments into playable MP4 videos. Your video and audio files are processed on device and do not need to be uploaded.

The app scans local .m4s files, helps batch pair matching audio and video fragments, exports standard MP4 files, and makes the save location easier to understand. It is intentionally focused on M4S pairing and export instead of trying to be a universal video downloader or all-format converter.

Key features:

• Process M4S files locally without uploading user files
• Batch pair audio.m4s with video.m4s
• Fix no-sound video.m4s cases when the matching audio.m4s is available
• Convert a single M4S file when needed
• Scan local folders for M4S files
• Keep conversion records
• Save converted MP4 videos to the system gallery

Best for:

• Fixing a video.m4s file that has no sound by merging audio.m4s
• Exporting multiple separated audio.m4s and video.m4s sets as MP4 files
• Opening an M4S file that will not play normally
• Avoiding online upload for private video files

If the source folder does not contain the matching audio fragment, the exported video may still have no sound. Please make sure the related audio.m4s and video.m4s files are both available locally.

Compliance note: only process local files that you own or have permission to use.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/