When I strap my phone to my stem the arrow points to 2 o’clock not where I should be turning.
Take phone off stem and direction arrow points the right way.
Ive just noticed that the arrow is surrounded by a red circle on the bike and green off.The compass points the right way.
What gives?

Ok, logic says the compass should go awry too, but Lord knows what electronics are used to work that simple principle out on a mobile…

So I’ll go with the “obvious” and say there might be something magnetic near the mobile, or that the sheer amount of metal near it is messing one of the numerous sensors up.

Edit: Not sure what app your using there but I would look at the online manual as it should be very clear what the red circle signifies with the info in front of you.

Or your in the Bermuda Triangle! 😉