A duet or side-by-side video puts two clips in one frame — you next to someone else's video, or two of your own camera angles playing together. It's the format behind reactions, collabs, tutorials, and "watch this with me" clips. There are two clean ways to make one on iPhone: use TikTok's built-in Duet, or record your own two-panel video with DualCam and lay the feeds side by side in an editor. Here's when to use each.
What a duet / side-by-side video is
The idea is simple: two video panels on screen at the same time. Usually they sit left/right or top/bottom, each filling half the frame. In a classic duet, one panel is someone else's existing clip and the other is you reacting or performing alongside it. In a DIY side-by-side, both panels are yours — for example your face next to what you're filming, or two lenses of the same moment. Whatever the mix, the whole effect depends on one thing: the two panels staying in sync.
Option A: TikTok's native Duet
TikTok has its own Duet feature built into the app. It only works with videos already posted on TikTok that allow duets, and it splits the screen for you automatically — the original clip on one side, your camera on the other.
- Open the TikTok video you want to duet and tap Share.
- Choose Duet from the menu (if the creator has enabled it).
- Pick a layout — left/right, top/bottom, or a green-screen style.
- Record your side; TikTok plays the original in sync as you film.
- Add sound, captions, and post.
Duet is quick and needs no editor, but it lives entirely inside TikTok: you can only duet TikTok videos, and the result is a TikTok post. If you want to duet something that isn't on TikTok — a friend on a video call, your own gameplay, a clip destined for YouTube or Reels — you'll need to build the side-by-side yourself.
Option B: make your own side-by-side with DualCam
To create a duet-style video without relying on TikTok, you capture your side cleanly first, then place it next to the other panel in an editor. DualCam makes the capture half easy: using Apple's Multi-Cam system (iPhone XS and newer, iOS 17+), it records two cameras at once — front + back, or two rear lenses — in a single take, with a draggable Picture-in-Picture preview so you can frame both feeds before you hit record.
- Open DualCam and grant camera and microphone access.
- Pick your pairing: front + back (you reacting to what's in front of you) or two rear lenses (wide + telephoto of one scene).
- Drag the Picture-in-Picture inset to frame both feeds; swap which lens is the main view mid-recording if you need to.
- Tap record once. DualCam captures both streams together, in sync, up to 4K at 60fps in HEVC or H.264.
- Stop. Your footage saves to Photos as separate files, ready to arrange.
Then open any editor (iMovie, CapCut, Final Cut), drop your DualCam feed on one track and the other panel — a collaborator's clip, screen recording, or your second camera file — on the second track, and position them left/right or top/bottom. That's your duet frame.
Why one take keeps perfect sync
The hardest part of any side-by-side is timing. Film two clips separately and their audio drifts, the beats never quite line up, and you spend the edit nudging tracks frame by frame. Because DualCam records both cameras in a single take, the two feeds share one clock — they're locked frame-for-frame with matching audio. When you split them into two panels, they stay in sync with no manual work. For the full recording flow, see how to record two cameras at once on iPhone.
Which method to use
| You want to… | Use | Why |
|---|---|---|
| Duet an existing TikTok video | TikTok Duet | Native, auto split-screen, no editor |
| React with both your cameras | DualCam + editor | Front + back in one synced take |
| Duet a non-TikTok clip | DualCam + editor | Combine your side with any video |
| Post the same duet to YouTube too | DualCam + editor | You control the file and aspect ratio |
DualCam's role is capturing your side — and both your cameras — cleanly; the actual two-panel duet frame is assembled in your editor of choice. That gives you a duet you can post anywhere, not just inside TikTok.
Vertical framing tips for duets
- Split down the middle. For a 9:16 vertical duet, each panel is short and wide — keep faces high in each half so they don't get cropped at the seam.
- Leave headroom. A little space above the head reads well and gives room for captions along the top or bottom.
- Mind the safe zone. TikTok, Reels and Shorts overlay buttons on the right edge and captions along the bottom — keep key action clear of those strips.
- Match the light. The front camera is usually darker; add a little light on your face so both panels look consistent.
- Shoot high resolution. Recording at 4K gives you room to crop each panel without softening the image.
DualCam can also save a 9:16 vertical and a 16:9 horizontal file from the same take, so your duet fits both a phone feed and YouTube. It even has built-in YouTube upload for the wide version.
Get started
Duets don't have to live inside one app. Whether you're layering two of your own cameras or combining your side with someone else's clip, it starts with a clean, synced capture. Learn more about split-screen video on iPhone and how to make reaction videos, then download DualCam on the App Store to shoot your side.