Wondering why videos won't play on your iPhone? Chances are that your device doesn't support the file format of the video you want to watch. By default, your iPhone works only with .m4v, .mp4, and .mov file formats for videos. But if you've just downloaded a video from the web, it's likely saved in either .avi or .mkv. The built-in apps like Photos and Files just won't play such a video.

Don't worry, our free Documents app can play all your favorite videos. Documents is the best iPhone video player app, file manager, and downloader, which supports the playback of numerous file formats for your movies, tv shows, and other videos: .3gp, .l16, .m3u, .m4v, .mm, .mov, .mp4, .scm, .avi, .mkv, .flv.

Video Player for iPhone and iPad

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How to play .avi, .mkv, and other video formats on your iPhone:

  1. Get Documents from the App Store and launch the app.
  2. To add your videos, tap the purple plus button at the bottom right.
  3. Choose where to import the files from. You can add videos from the Files app, any cloud storage, or even your computer.
How to play video format on iPhone and iPad
  1. Select the desired video. Now, it's available in Documents.
  2. Tap the video file to play it.

You can double-tap the right or left part of the screen to fast forward or backward the video by 10 seconds.

The Documents app also lets you change the playback speed for .mp4, .mpv, .3gp, .m4v, and .mov video files.

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How to watch videos with subtitles on your iPhone:

Besides supporting numerous file formats, Documents makes it easier to watch videos with subtitles. The app works both with embedded subtitles and subtitles from an external source.

Here are the supported formats:

  • External subtitles work with the following video formats: .avi, .mkv, .flv, .ogg, .mpg, .mpeg, .ts.
  • Documents works with .srt, .sub, .ssa, .ass, .pjs, .rt, .smi, .stl subtitle formats.
  • The app supports external audio files in .mp3, .aac, .m4a, .m4b, .m4p, .m4r, .amr, .ac3 formats.

How to watch a video with subtitles:

  1. Put the video file and the subtitle file in the same folder. Learn how to create folders in Documents.
  2. Make sure the titles of the related video and subtitle files coincide or start with the same sequence of letters (e.g. some_name.mkv and some_name_subtitle.srt).
  3. Open the video.
  4. Tap the subtitles icon at the bottom right of the player.
How to enable subtitles on iPhone and iPad
  1. Select the desired subtitle file and tap Done.
  2. That's it! Enjoy the movie with subtitles.

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Now, you don't need to worry that videos won't play on your iPhone. With Documents, you can watch videos in numerous formats and even play .avi and .mkv on your iPhone. The app also has a built-in browser so you can download your favorite movies from the web.

Download Documents for free and enjoy the best video player for iPhone!