Can you use Back Tap to start a dual camera recording on iPhone?
Partly. Back Tap can take you from almost any screen straight into DualCam with two or three taps on the back of the phone, which is a genuinely fast way in. What it cannot do is skip past that and drop you directly into a running recording, because that would need DualCam to offer a dedicated Shortcuts action for the tap to trigger, and it does not have one.
Back Tap is not the same feature as the Action Button, and the difference matters here: it lives in Accessibility settings rather than on a physical switch, which is why it is worth knowing about even on an iPhone that has no button to reassign.
What Back Tap actually is
Back Tap lives in Settings > Accessibility > Touch > Back Tap, and it turns two taps or three taps on the back of the phone into a trigger for one assigned action each — Double Tap and Triple Tap are independent, so they can point at two different things. Apple ships a fixed list of system actions it can trigger: Home, App Switcher, Control Center, Notification Center, a screenshot, Reachability, mute, scroll gestures and more. Separately from that list, it can also run a Shortcut.
Running a Shortcut is the door a third-party app comes in through. A Shortcut that opens a specific app is available to any app on the phone, DualCam included, without that app doing anything special to support it. A Shortcut that does something more specific — like telling an app to start recording — only exists if the app has published its own named action through the Shortcuts app for one to be built around.
Opening DualCam is real; starting the recording is not
Setting either Double Tap or Triple Tap to Shortcut > Open App > DualCam works exactly like tapping the icon, just reachable from the Lock Screen or from inside another app with two or three taps on the case. That is a real shortcut for anyone who wants to get to the camera screen fast.
What is not on the table is a tap that goes further and starts the file rolling in the same motion. DualCam does not publish a Shortcuts action for starting a recording, so there is nothing for a Shortcut — Back Tap, the Action Button, or an automation you build yourself — to call beyond opening the app. That is the same ceiling the Action Button runs into, because it comes from the same missing piece on the app’s side, not from anything specific to either trigger.
The gap that is left is setup time, not the trigger
A multi-camera session has to configure two camera inputs against one shared hardware budget before either one produces a usable frame, and that negotiation happens before the session starts, not while it is already running. That is why the camera screen shows a brief loading moment even when opened normally, covered in more detail in the guide on why dual recording takes a moment to start.
Whatever opens DualCam — Back Tap, the Action Button, or just tapping the icon — still has to wait on that same configuration work underneath. A faster trigger saves the steps that come before the app opens, not the setup that happens after it does.
Double tap or triple tap: pick the one that will not fire by accident
Back Tap listens through the phone’s accelerometer, not a physical switch, so it has no way to tell a deliberate double tap on the case from two knocks that happen for some other reason — setting the phone down harder than usual, it shifting against something rigid in a bag, a case bumping a doorframe in a pocket. Double Tap is the easier one to trigger on purpose, and for the same reason, the easier one to trigger by mistake.
Triple Tap asks for one more deliberate hit, which cuts down on accidental launches without making the gesture noticeably slower to do on purpose. If Double Tap is already carrying a system action worth keeping — a screenshot, Control Center — Triple Tap is the one to hand to DualCam.
What actually shortens the gap
- Set Triple Tap, not Double Tap, to Shortcut > Open App > DualCam, so a knock in a pocket or a bag does not launch the camera on its own.
- Set the countdown timer before a take you know is coming — off, 3, 5 or 10 seconds. It has to be chosen before recording starts, but once it is, it absorbs the remaining setup pause instead of you standing there watching the preview load.
- For several short takes back to back, stay on the camera screen between them instead of backing out and relaunching. Reopening the app is what throws away the configuration work the session already did; leaving it open keeps both cameras already running.
Common follow-up questions
Do I need an iPhone with the Action Button for this to work?
No. Back Tap is a separate Accessibility feature reached through Settings > Accessibility > Touch > Back Tap, not tied to the Action Button or to any one physical control.
Can Double Tap and Triple Tap each do something different?
Yes. They are two independent triggers, so one can open DualCam while the other keeps doing whatever it was already set to, like taking a screenshot or opening Control Center.
Could Back Tap ever jump straight into a running recording instead of just opening the app?
Only if DualCam published a Shortcuts action for starting a recording, which it does not today. Even then, the multi-camera session would still need to configure both cameras before producing a frame, so the tap would remove the step of opening the app, not the setup itself.
Want to just do this?
DualCam records the iPhone front and back cameras at the same time and writes one finished MP4 while you shoot. Free, no account, no ads, nothing leaves the phone.