Canon EOS-1D X Mark III Advanced User's Manual page 519

5.
Set [Bluetooth] to [Enable].
6.
Select [Pairing].
7.
Select an option.
If Camera Connect is already installed, select [Do not display].
If Camera Connect is not installed, select [Android] or [iOS], scan the
displayed QR code with the smartphone to access Google Play or App
Store and install Camera Connect.
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