my phone compass point in a different direction,why?

[Profpointy]

Do you have the new emergency number on speed dial, or memorised? 😉

I use Trail Sense as phone compass app & it shows sun and moon positions on the compass ring, as a check.

What is "new emergency number"?

 

[mjr]

What is "new emergency number"?

0118 999 881 999 119 725 3

Sorry, it was the mention of turning a phone off and on again that brought the memory back. Shame about _that_ episode of "The IT Crowd" though.

 

[Profpointy]

0118 999 881 999 119 725 3

Sorry, it was the mention of turning a phone off and on again that brought the memory back. Shame about _that_ episode of "The IT Crowd" though.

Ah not seen the episode, but I get the joke !

 

[andrew_s]

To tell whether your phone or GPS is using a magnetic compass or is getting directions from the movement it detects, just hold or mount it so it's upside down - i.e. the top of the screen is closer to your body.

If it's using a magnetic sensor, it won't be fooled and will continue to indicate that north is ahead of you when riding northwards along a north/south road.
If it's using detected movement, it will assume that the detected northwards travel is towards the top of the screen, and will indicate that south is ahead of you.

Even if there is a magnetic sensor, a phone or GPS will often use detected movement in preference to the magnetic sensor when you are moving at a reasonable speed (cycling - i.e. faster than walking). They do this because it's not affected by things like the steel in your bike or car, and it uses less battery power too.

 

[lazybloke]

Alsi explains why Google Maps is terrible for walking: it never knows which way you're facing at the start.

Google maps has supported magnetometers since 2010. If you phone has an "electronic compass", Maps will show where you're facing, whether walking or standing still (including "at the start").

Many bike computers lack this functionality, which is occasionally quite annoying.