Rootbly - AI Subtitle
YouTube Video Translator
About
Watch foreign YouTube videos with AI-generated translated subtitles in real-time. Paste a URL to get instant subtitles in your preferred language, with options to adjust sync, size, and view original text.
What's New in Rootbly
2.1.0
September 28, 2026
What's new in 2.1.0 • Dark mode • Redesigned sign-in screen • All subtitle settings in one sheet, plus a quick-adjust bar in fullscreen • Rate subtitle quality right from the player Fixes • Original-language subtitles now follow your font size setting • YouTube's built-in captions no longer show on top of our subtitles • Guests are no longer signed out unexpectedly
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FAQ
What languages does Rootbly support for subtitle translation?
Rootbly supports AI subtitle translation for 15 languages, including English, Korean, Japanese, Chinese, Spanish, and French. The app's UI is also available in Korean and English.
Can I adjust the subtitles in Rootbly?
Yes, Rootbly offers subtitle sync control, allowing manual offset adjustment within a ±5 second range. You can also customize subtitle size with presets and fine-grained control.
Does Rootbly have ads?
No, Rootbly does not contain advertisements. It also offers YouTube Premium integration for an ad-free viewing experience.
How does Rootbly handle translation progress?
Rootbly provides real-time progress tracking for each translation stage: downloading, transcribing, and translating. You will receive push notifications the moment translation is complete.
Can I find YouTube videos directly within Rootbly?
Yes, Rootbly includes a YouTube search feature, allowing you to find videos directly within the app. You can also browse channels, playlists, and live streams.
What devices is Rootbly available on?
Rootbly is available on iPhone and iPad devices.
How often is Rootbly updated?
The latest version of Rootbly is 2.1.0, which was last updated on September 28, 2026. This indicates a relatively active development cycle.
Is Rootbly suitable for younger users?
Rootbly has an age rating of 4+, making it suitable for a wide range of users, including younger audiences, when supervised.
