Recording iphone screen while running app on xcode

Yes, open quicktime and next.. ⌘ + ⌥ + N, in the screen click on the record button arrow and choose your device.

EDIT: from iOS 11 you can record the iPhone screen enabling the screen record.

1. Launch Settings, and select Control Center.
2. Add Screen Recording.
3. Swipe-up from the bottom of the display to reveal Control Center.
4. Tap Screen Recording button.

Use QuickTimePlayer:

1. Connect iDevice to Mac.
2. Open QuickTime
3. File > New Movie Recording
4. If you don't see your screen mirrored immediately, go to the dropdown arrow next to the record button and select Camera > iDevice

If you are recording from iOS Simulator:

1. Start everything up in iOS Simulator
2. Open QuickTime
3. File > New Screen Recording
4. Press record button. You will now be given the option to drag out an area of the screen to record.

To take a screenshot, use the screenshot operation:

xcrun simctl io booted screenshot

To record a video, use the recordVideo operation:

xcrun simctl io booted recordVideo <VideoFILENAME>.<extension>

UPDATE

Using the new release of Xcode 12.5 you can simply record the simulator screen using ⌘ + R.

or as bellow:

1. Launch Simulator app.
2. Open File menu > Record Screen

3. Recording indicator will show up on the upper right of the title bar. You can begin your recording after the indicator showing up.

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