Presub Downloads & RevenuePresub — Video Subtitles · App Store

Turn what a video says into original and translated subtitles.

This is not live interpretation. Subtitles are built ahead of playback and kept, so wherever you rewind to, the captions are already there. What you build is saved and reopens instantly.

■ It all happens on your device
Speech recognition and translation both run on this iPhone. No server, no account, no login. The audio never leaves your phone.

■ Rewind and the subtitles are still there
When you want to hear a line again, a live-captioning app cannot caption sound that has already passed. Presub builds captions ahead of playback and keeps them, so they are there when you rewind or reopen.

■ Original and translation together
Read what you hear next to what it means. Choose which one is larger and how big the text is. Move sentence by sentence, "Repeat this line", or slow playback down. Keep listening with the screen off, and skip to the previous or next line from the Lock Screen.

■ A whole textbook as one set
For textbooks with many tracks, like TOEIC and TOEFL listening audio, select the files together or pick a folder and they're saved as a set. Pick up where you left off from the track list, and the next track starts when one ends. The original and translation appear for each line. Press and hold a line you missed to repeat only that line. Press and hold an unknown word to look it up instantly. Add words that often get misheard, like names in your textbook, to "My Words" and they're used as hints for speech recognition.

■ Dictation
Listen with the original text hidden, and playback pauses at the end of each line. Write it down, check it with "Show Text", and save the lines you found hard to Review in one go.

■ Save and review
Save sentences and words from subtitles to gather them in the "Review" tab. Move expressions you have memorized to "Learned", mark difficult ones with a star to filter by "Difficulty", and "Review with cards". Listen again with device audio, and export to Anki/CSV.

■ The subtitle list is a transcript
Open the sentences as a list, read back through them, and tap one to jump to that moment. Export as an SRT subtitle file or plain text.

■ Not just English
Speech in Korean, English, Japanese and Chinese becomes subtitles, translated between them. Keep the original and the translation side by side and read it like a script.

■ Featured channels
Open public broadcasts such as the U.S. Federal Reserve's FOMC press conferences, NHK news and Taiwan's Legislative Yuan right inside the app.

■ What you can open
Video and audio files on your device, and unprotected web video opened in the app's browser. Protected video (YouTube, Netflix and the like) is not supported.

Languages: Korean · English · Japanese · Chinese (Traditional)

Free for 3 new videos a day. Within a set, each track counts as one video. Video length is not counted, and reopening subtitles you already made is not counted either. You can save up to 30 expressions in "Learning" for free ("Learned"