IAN LANG ELECTRONICS
1. Direction finder shows wrong direction.
Your phone is near a magnetic field affecting the magnetometer. Loudspeakers can do this as can live wires at high voltages. The Earth's magnetic field is weak and the magnetometer can be confused by a stronger magnetic field nearby.
Particularly for the Sony Xperia range but also for other phones: the magnetometer can go haywire. Recalibrate it by waving the phone about in a figure-of-eight pattern with the top of the phone facing upwards in your hand.
Remember the direction is MAGNETIC not true North.
2. Slow map refresh.
This is caused by your internet connection speed. In testing, between one and seven seconds was normal, the latter being on a slow broadband wi-fi in a semi-rural location in Yorkshire.
3. Slow pickup of GPS
This happens indoors. Outside GPS pickup is very rapid. If your car has an isothermic windscreen it can block GPS too. Put the device near a window.
4. Can't scroll the map.
Put the slider to the left so that it shows red.