Yes, BitTorrent Web supports 2 different types of subtitles
1. Subtitles embedded in the movie file
2. Subtitle files that you load from external sources (SRT files)
INSTRUCTIONS TO LOAD EXTERNAL SUBTITLES (ex. SRT files)
1. Click on the "cc" icon in the lower right corner of the video player. See image below.
2. Click on the "+ Subtitles track" button
3. Locate and select the SRT file for the movie you are watching
4. BitTorrent Web loads the SRT file in to the video player
5. Select the subtitle you want to display on your video player