Casio WSD-F10 User Manual page 52

Magnetic North and True North
North indicated by this watch under initial default settings is magnetic north.
If you want the watch to indicate true north, you need to use an Android
smartphone to configure required settings. See
Settings" for details.
Important!
Magnetic north is always indicated while the watch is connected with an
●
iPhone. Changing to true north is not supported in this case.
"TOOL Button and TOOL App
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