I'm posting a request to ask for the possibility to draw arrow in a free style maner. Actually, an arrow is either up or down 
To draw an arrow to pin point an area, I'm using 3 trend lines 2 of them to create the arrow at the end of the line
All the code to draw a trend line is already in place. You only need to replace the Trend line by an arrow. 
That should not be to complicated :)