UI improvements

[DaneEvans]

• The jitter in the mag sesor is considerable (+- .5 on my desk ) either improve filtering, or reduce the display precision to 0dp, and target range increase to match.

• Either allow any 'top edge' using the accelerometers to determine which is currently acting as it, or Add an arrow / bar on the top edge of the screen, and change it to 'place the red bar against the top edge of your panel'