BurninTranscription runs on the phone
Burnin does not send your video anywhere. Apple's on-device speech transcriber turns speech into text right on the iPhone, which is why captioning keeps working on a flight, underground, or with the data switched off.
Features
Everything Burnin does
Grouped the way a video happens: import it, transcribe it, edit it, export it. Everything on this page works with no account.
On the phone, with no signal
Language packs, downloaded once
The first time you transcribe in a language, its model downloads. After that it stays on the phone, and every video in that language transcribes with no connection at all.
The only download is the language pack
Burnin doesn't fetch any other model. Segmentation, gap retries, editing and export all use what's already on the phone.
Automatic language detection
Burnin detects which language is being spoken on its own. A manual picker is there for when you would rather choose, or when a video mixes languages in a way detection cannot resolve on its own.
Transcription and captioning
Speech to readable caption chunks
A raw transcript is automatically segmented into caption-length lines, so what appears on screen reads at a glance instead of running on as one long sentence.
Gap detection that tries again
Burnin looks for stretches of five seconds or more with no caption, where speech likely got dropped. It transcribes just that stretch a second time, folds any words it finds back into your captions, and leaves a stretch that's really silent empty.
Every voice, captioned in order
Burnin captions everyone who speaks, in the order they speak. It doesn't label who's talking, so if a conversation needs names or a dash at each new voice, you add them in the editor.
Gap retries run on the phone too
Segmentation and gap detection need no network signal at all, and a gap retry uses the same on-device transcriber and language pack as the first pass.
The caption editor
A full editor sheet for every caption
Tap a caption, or the add button floating over the list, to open a large editor sheet at full height from the first frame, with its own delete control and a "Done" to close it.
A new caption lands where you are
Add a caption and it is inserted at the video's current position, in chronological order alongside its neighbors, not always tacked onto the end of the list.
Drag-trim on a visual timeline
Each caption's start and end time is a handle on a timeline strip. Drag either edge to retime it against the video underneath, with a margin above and below every block so there is always room to start a pan.
A draggable playhead
Drag the playhead on the timeline to scrub the video directly, instead of only watching it play. Hold it near either edge and the timeline scrolls along, so the playhead stays on screen even in a longer video.
Neighbor-clamping
Dragging one caption's edge past its neighbor is not allowed. Captions cannot be made to overlap by accident.
Undo and redo, deep
Every text edit and every trim is on the undo stack, twenty to thirty steps back, so an experiment you don't like is one gesture from gone.
Auto-save, debounced
Edits are saved automatically roughly every 600ms as you make them. Closing the app mid-edit, or a call coming in, does not cost you the work.
Live preview with captions burned in
The video preview shows exactly what the exported file will look like, captions and all, updated as you edit.
Title and description, before you share
Written from your own transcript
Right after export, before the share sheet opens, Burnin offers a title and a short description with a couple of hashtags, generated from the captions you just edited, not re-transcribed from scratch.
Three tones to pick from
Neutral, balanced, or clickbait. Switching tone regenerates the title and description to match, and you can skip the screen entirely and export with just the video.
Apple Intelligence, on the device
Generation runs through Apple's on-device Foundation Models when available, so the transcript never leaves the phone to be summarized.
A fallback with no capability gate
On a device without Apple Intelligence, or if generation fails, an on-device heuristic takes over: it picks a named person, place, or organization from the transcript for the title, and the single most information-dense sentence for the description, never just the first line.
Crop and export
Four crop options
Original, 9:16 for Reels, TikTok and Shorts, 1:1 for square feed posts, or 16:9 widescreen. Pick the shape the destination actually wants.
Three export resolutions
720p, 1080p or 4K, with captions burned directly into the exported video rather than added as a separate track.
Captions burned in, with an SRT if you want one
The video export is a single file with the captions part of the picture, so it plays correctly anywhere without a subtitle track attached. If you need the captions as text too, the SRT button in the editor exports them as an .srt file you can share.
A notification when it's done
When a transcription or an export finishes, Burnin lets you know with a notification, so you don't have to keep checking. It comes from the phone itself, not a server, and only if you've allowed notifications.
Projects
Every video becomes a project
Import a video and it becomes a project in your library, with its captions and edits kept alongside it.
Draft or Exported, at a glance
Every project in the Library shows whether it's still a Draft or already Exported, with the video's length on the date line beside it.
Rename and delete
Rename a project to find it later, delete one you no longer need, or select several at once to clean up in bulk.
Recovers a missing source file
If the original video file goes missing locally, Burnin can recover it from your Photos library instead of leaving the project broken.
Stored on your phone, not a server
Projects are stored locally, on-device. There is no cloud sync and no account for them to belong to.
Different by default, not bolted on later
Most caption apps run in the cloud because that is the easier engineering path, not because your video needs it to. Burnin does the same job the other way around.
| Comparison | A typical cloud captioning app | Burnin |
|---|---|---|
| Where your video goes | Uploaded to a server to be transcribed | Stays on your phone, transcribed on-device |
| Account | Sign-up required to export | None, ever |
| Internet connection | Needed every time you transcribe or export | Only once, to download a language model |
| Price | Often a subscription for full-length or HD export | No subscription, no ads |
Four aspect ratios, one export
A video shot for one place rarely fits another. Burnin crops and exports for the shape a platform actually wants, with captions burned in to match.
Original
Untouched
The source video's own aspect ratio, no crop applied.
9:16
Reels, TikTok, Shorts
Full-height vertical crop for short-form video.
1:1
Square
A square crop for feed posts.
16:9
Widescreen
Standard landscape, for everywhere else.
Three exports, one source video
Higher resolution means a bigger file and a longer export, and Burnin shows you that trade before you commit to it rather than after the export has already started.
720p
Smallest file, fastest export
1280×720
Frame size
Fast
Export speed
1080p
The usual choice
1920×1080
Frame size
Balanced
Export speed
4K
Full detail, largest file
3840×2160
Frame size
Slowest
Export speed
Privacy by construction
No account, no ads, no tracking
Importing, transcribing, editing and exporting all happen on your phone, and every project stays there. There is no sign-in, so there is nothing to sync and nowhere for a video to go but your own device.
- No advertising, no advertising identifiers, no third party analytics SDK.
- No account, no login, ever.
- No cloud sync. Projects are stored locally, on-device only.
- Transcription, editing and export all run on the phone, offline once the language pack is downloaded.
What leaves your phone, and when
| Importing a video | Nothing. The video is read from Photos or Files and stays on the phone. |
| Downloading a language pack | A request for that language's model file only. No account, no identifier. |
| Retrying a dropped stretch | Nothing. The stretch is transcribed again on the phone, with the language pack that's already there. |
| Transcribing, editing | Nothing. All of it runs on the phone. |
| Exporting a video | Nothing. The captioned file is written to your phone. |
What it needs to run
On-device transcription needs a fairly recent Neural Engine, so Burnin supports iPhone 12 and later. Older devices, and the Simulator, are not supported. Burnin runs on iPhone and iPad, though the app is not iPad-optimized yet. An older iPhone can still open a project to write captions by hand or bring in a ready-made subtitle file; it just can't transcribe speech itself.
Why on-device rather than a server
Sending video to a server would mean an account, a connection, and someone else's copy of your footage sitting somewhere. Running transcription on the phone means none of that has to exist. It costs a one-time model download and it means the oldest supported iPhones do the work themselves rather than a cloud doing it for them.
Requirements
| Platform | iPhone and iPad (not iPad-optimized yet), iOS 26.0 or later |
|---|---|
| On-device transcription | iPhone 12 and later. Older devices, and the Simulator, are not supported |
| Video formats | MP4, MOV |
| Max video length | No set limit. A longer video takes longer to transcribe and export |
| Account | None. Not required, not offered |
| Price | No ads, no subscription |
One thing captions are not
Automatic transcription is not perfect on any device, on any app. Burnin's editor exists because every caption is meant to be checked, not accepted blindly, and gap detection is a heuristic that reduces missed speech rather than a guarantee that none is ever missed.
Captions burned in, never sent out.
For iPhone, on the App Store. No account needed to use it.