Does tapping to focus affect both cameras, or just one?
Just one — whichever camera's image is under your finger. Tapping the main frame in picture-in-picture focuses and exposes for the main camera only; the small inset keeps running its own autofocus untouched until you tap that too. Tapping the top half of a split screen does the same for the top camera alone, leaving the bottom half exactly as it was.
This is not a limitation someone chose. The front camera and the back camera are two separate pieces of capture hardware, each with its own focus and exposure system running independently of the other. A dual recording draws both of their images into one frame, but underneath that composited picture there are still two cameras that have never been able to share a single focus point, because they never needed to before there was a reason to put them side by side.
Two cameras, two focus systems, long before compositing
Every camera on an iPhone runs its own continuous autofocus and auto-exposure, adjusting for whatever that specific lens is pointed at. That has always been true — a single-camera app only ever shows you one of these systems at a time, so there was never a reason to notice that the other one exists and behaves the same way, independently.
A dual recording does not change that architecture. It takes two already-independent camera feeds and draws them into one frame on the GPU. The compositing happens after each camera has already decided its own focus and exposure — it is a layout step, not a step where the two cameras start listening to the same instructions.
What a tap actually does
Tap the frame you want sharp, and exposure compensation rides along on the same gesture — that is the whole control, the same one-tap-to-focus gesture the stock Camera app uses. What is different in a dual recording is that the screen now shows more than one camera's image, so the same tap has to be routed to whichever camera actually owns the pixels under your finger.
That routing is not a compromise; it is the only sensible behaviour. There is no single point in space that means anything to two lenses pointed in different directions at different subjects. A tap has to belong to one camera, because the thing you are trying to make sharp only exists in one of the two images.
What that looks like in each layout
Picture-in-picture
Tap anywhere in the large main frame and the main camera refocuses and re-exposes for that spot. The small inset in the corner is a completely separate image from a separate camera, so it keeps whatever focus and exposure it already had. If the inset needs attention — a face that has drifted into shadow, a background that just changed — it needs its own tap.
Split screen, top-and-bottom or left-and-right
The same rule applies across a split. A tap in the top half only ever reaches the camera drawing the top half; the bottom half's camera does not know the tap happened. This is genuinely useful in a two-person interview shot side by side: each half can be focused and exposed for the person in it, on their own schedule, without the other side's picture flinching every time you adjust one side.
Where this actually matters: two very different scenes
The clearest case is a reaction shot where the back camera faces a bright window and the front camera sits in a dimmer room. Those two images have nothing in common exposure-wise, and they never will, because they are two different scenes being lit by two different amounts of light. Tapping the bright side to pull exposure down does nothing for the dim side, and it should not — pulling the dim side down along with it would just make a well-lit face go dark for no reason. Each half earns its own tap because each half is genuinely a different photographic situation.
What tapping cannot do
It cannot make the two cameras share one exposure value or one focus plane, because there is no version of "both at once" that means anything when the two lenses are pointed at different things from different positions. It also is not related to which lens is active on the back camera, or to zoom level — those are separate controls, covered in the guide on zooming and switching lenses while recording — tap-to-focus only ever moves the focus and exposure point within whichever image you touched.
Common follow-up questions
Does exposure compensation follow the same per-camera rule as focus?
Yes. Tapping sets both focus and exposure for the same spot in the same gesture, and both apply only to the camera whose frame you tapped — the other camera's exposure is untouched.
Can I tap once and have it apply to both cameras?
No, and there is no setting that changes that. The two cameras are separate hardware with separate focus systems, so setting both takes two taps — one on each camera's part of the frame.
Is this different from how tap-to-focus works in the stock Camera app?
The gesture itself is identical to the one-tap focus-and-expose you already know from the stock Camera app. The only difference is that a dual recording puts more than one camera's image on screen, so the same tap now has to be aimed at the one you mean.
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