I also have the problem regarding the altitude. The locations, which are near to each other, their displayed markers overlap. That is, one of the labels to be displayed disappears behind the other message label. Can you guide me through this?
You can specify offsets in both x and y direction for drawables to move them away from there original geo location. In case you're designing something like a marker that is composed of multiple drawables and two such markers behave strangely (overlap) when showed at the same position, you can group them together be setting the zOrder property to a common value (a common value for one such marker). This way only all the drawables of marker A or B are shown together and hide the other.