Apple Users

Ocelot II

(126,102 posts)

12. That's how non-digital, "real" compasses work - they indicate magnetic north.

Thu Apr 20, 2023, 05:00 PM

Apr 2023

The app just simulates an ordinary magnetic compass, which was used in all kinds of navigation until the invention of GPS. The advantage of a regular mag compass is that it's self-contained, unlike GPS, which relies on satellite signals and an internal electrical source. So if you want to calculate a true course using a mag compass, you just have to consult a declination chart so you know what the variation between true north and magnetic north is at your location.

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I just discovered my iPhone "compass" app. [View all] WheelWalker Apr 2023 OP

It shows magnetic north. Ocelot II Apr 2023 #1

So it does. And subject to local attractions, as well. WheelWalker Apr 2023 #5

That's how non-digital, "real" compasses work - they indicate magnetic north. Ocelot II Apr 2023 #12

It also has an altimeter and your gps location... ret5hd Apr 2023 #2

It is magnetic Jerry2144 Apr 2023 #3

So it is. I would never have imagined so. How bizarre. WheelWalker Apr 2023 #6

It's easier to measure with a couple magnetic coils Jerry2144 Apr 2023 #8

Ah, I suspected something along those lines but don't know enough about anything WheelWalker Apr 2023 #9

You're welcome Jerry2144 Apr 2023 #11

I checked the altimeter with a known source and it is a foot or so off..not bad.. mitch96 Apr 2023 #4

I collect lots of apps. I look for the daily "gone free" and discounted apps. usonian Apr 2023 #7

It's almost unbelievable. WheelWalker Apr 2023 #10