DroidDiagram version 1.1.1 adds the following new features:

Improved arrowhead rendering
~ arrowheads are rendered as a single path when possible and several arrowhead Shape definitions has been changed to implement mitered joints when HeadPen is set to a thick pen.
~ the point where end segments connect to arrowheads can be specified via the Shape.LinkSegmentInset property. Shape definitions from the ArrowHeads class set it to suitable default value. This allows using transparent or semi-transparent brushes without seeing the link line drawn behind arrowheads.
~ arrowhead shadows are no longer filled if the link's EffectiveBrush is null or fully transparent.
~ IntermediateHeadShape is now also rendered for Bezier links.

Miscellaneous
~ link segments and node borders are now drawn anti-aliased.
~ improved DiagramLink rendering speed.
~ improved text layout in TextComponent and LinkLabel.
~ fixed null-reference exception in some situations when tap is outside of diagram boundaries.

If anyone is interested in trying the beta version, please download this archive containing the updated jar file:
https://mindfusion.eu/_beta/DroidDiagram.1.1.1.zip

Any comments, questions and general feedback are welcome.