Why do saved dual camera recordings take up double storage on iPhone?
Short answer: because Save copies the file rather than moving it. The recording you already had in DualCam’s own library does not disappear once a copy lands in Photos — it stays exactly where it was, and now the same footage exists on your phone twice. Nothing is broken or leaking; the app simply never wired the two libraries together.
This only becomes a problem once it is invisible. A handful of saved ten-second clips duplicated in two places is nothing. An hour of a driving vlog or a study session, saved months ago and forgotten about in the app’s own library, is a multi-gigabyte copy sitting somewhere you stopped looking. Once you know where it is, getting the space back is a one-tap job, not a mystery.
Save copies the file — it does not move it
DualCam keeps every take inside its own library the moment recording stops, with a thumbnail you can open and scrub through. Save and Share are both ways of sending a copy of that file somewhere else — Save writes it into Photos, Share hands it to the iOS share sheet — but neither one touches the original. The recording you started with is still sitting inside the app afterwards, unless you go in and delete it yourself.
That is a deliberate choice, not an oversight. If Save deleted the app’s copy the instant it finished, a save that got interrupted, or a decision to also send the same clip to an editing app an hour later, would have nothing left to work from. Keeping the original in place until you explicitly remove it is what makes Save and Share safe to use more than once on the same recording.
What the second copy actually costs
DualCam’s composited video runs at roughly 10 Mbps, which works out to about 75 MB per minute, a little over 4 GB per hour — the same number whether you shot at 720p or 1080p, since capture resolution changes detail, not the size of the canvas being written. That is the cost of one copy.
A saved take you have not deleted from the app is paying that cost twice. An hour-long session sitting untouched in both DualCam’s library and Photos is roughly 8 GB for one piece of footage, not 4 — and because the app’s own library is easy to forget about once a clip is safely in your Camera Roll, that second copy is usually the one nobody remembers to clear out.
Actually freeing the space
Confirm it saved before you delete anything
Open Photos, or wherever you shared the clip to, and check the video is actually there and plays correctly before removing anything from DualCam’s library. Once you delete the app’s copy, that is the only version left — there is no way to pull a fresh one back out of the app afterwards.
Delete inside DualCam, not just in Photos
The space you are trying to get back is inside the app’s own library, so that is where the deletion has to happen. Open the recording in DualCam’s built-in library and delete it there. Deleting the same clip from Photos instead does nothing to the app’s copy — the two libraries were never linked, so removing one is invisible to the other.
Share behaves the same way, with one difference
Sending a clip through the iOS share sheet to Files, Messages or a third-party app does not create a Photos copy at all — those are separate destinations, and only choosing Photos from the share sheet does what the dedicated Save button does. Either way, the app’s own copy is untouched no matter which destination you pick, so the same rule applies: freeing the space means deleting the take inside DualCam once you are done with it, regardless of how many places you have since sent it to.
Common follow-up questions
Does saving a recording remove it from DualCam’s library?
No. Save copies the file into Photos; the original stays inside DualCam’s own library until you open it there and delete it yourself.
If I delete a clip from Photos, does it disappear from the app too?
No. The app’s library and Photos are two independent libraries that were never linked together, so deleting a clip from one has no effect on the other.
How much space do I actually get back by deleting inside the app?
Roughly what the clip cost to record in the first place — about 75 MB per minute, a little over 4 GB per hour, since deleting it removes the second full copy of that footage.
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