What you will need:
• A Mac (running OS X Yosemite or later)
• An iOS device (running iOS 8 or later)
• Lightning Cable
Step 1:
Connect your iDevice (iPhone, iPad or iPod touch) to your Mac using the Lightning cable.
Step 2:
Open QuickTime on your Mac.
Step 3:
Go to File and select “New Movie Recording”.
Step 4:
A window will appear. Next to the record button, you will see a little arrow. Click that arrow and select your iDevice. If you want in-app sound in your video, select your iDevice as microphone.
Step 5:
Click on the red record button. Once you’re finished, tap the stop button and save. You’re done!
Hope this was useful. Happy landings!
Note: Another topic is already explaining how to record your iDevice screen but this one is an improved version.