subMatik
On-device AI subtitles
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
subMatik turns your iPhone into a complete subtitle studio. Drop in any video — vertical Reels, horizontal interviews, podcast audio — and get clean, timed captions in seconds. Transcription, burn-in, and export run on-device; translation is on-device with Apple Translation, or via Google/DeepL if you choose.
WHAT MAKES SUBMATIK DIFFERENT
• 100% on-device transcription via the Whisper speech model (WhisperKit). Your audio never touches a server.
• 70+ languages supported, including Turkish, Chinese (Simplified + Traditional), Japanese, Korean, Thai, Khmer, Lao, Burmese, and more.
• Context-aware translation. Each segment is translated alongside its neighbors so idioms and homonyms come out right.
• Vertical-friendly subtitle placement. The Position Picker has a 3×3 anchor grid + drag-to-tune fine adjustment over a real frame from your video — no guessing.
• Reels mode. Chops cues into 1–5 word bursts that read fast on phone screens.
• Burn subtitles into the video pixels. Export an MP4 with captions baked in, ready for Instagram / TikTok / YouTube Shorts. Save directly to Photos.
• Re-translate any existing SRT into a new language without re-running Whisper.
• Files-app integration. Right-click any video → "Open in subMatik" → ready to caption.
• No account, no ads, no analytics dragnets. Optional anonymous crash telemetry via Apple MetricKit only.
WHY ON-DEVICE MATTERS
Modern Whisper models run entirely on your iPhone. There's no reason to upload your private conversations, family videos, work recordings, or proprietary content to someone else's server just to get subtitles. subMatik proves that the highest-quality transcription can be the most private one too.
OUTPUT FORMATS
• SRT (universal, supported everywhere)
• Burned-in MP4 (subtitles in pixels, no separate file needed)
PRO TIPS
• "Upper third" position preset keeps subtitles clear of TikTok / Reels bottom UI.
• Long-press any file in the queue to set a custom subtitle anchor just for that clip.
• DeepL users: paste your API key in Settings for higher-quality translations on European languages.
• On first launch you choose a Whisper model — from a fast ~150 MB option up to the highest-accuracy one. It downloads once (use Wi-Fi). After that, transcription is fully offline.
REQUIRES iOS 26.0 OR LATER. Works on iPhone 11 and newer. Best experience on iPhone 14 Pro and newer.
PRIVACY POLICY: https://catheadai.com/submatik/privacy
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
• More accurate error messages — videos with no detectable speech now say so clearly instead of showing a storage error
• Cancelling during translation now cancels cleanly
• Fixed rare cases where an empty subtitle file could be written
The developer, Sevki Bugra Ozbek, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- User Content
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Sevki Bugra Ozbek
- Size
- 6.8 MB
- Category
- Photo & Video
- Compatibility
Requires iOS 26.0 or later.
- iPhone
Requires iOS 26.0 or later. - Mac
Requires macOS 26.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 26.0 or later.
- iPhone
- Languages
- English and Turkish
- Age Rating
4+
- 4+
- Copyright
- © 2026 Sevki Bugra Ozbek, CatHead AI