Syntree
Freeware, developed at the University of Groningen under the supervision of Mark de Vries and Leonie Bosveld-De Smet
Download Syntree tree drawing software (zip-file) here: syntree.zip
The application is platform-independent and runs on Java.
For Windows: extract and just click on SynTree.exe.
For Mac: only the syntree.jar file is relevant.
Example of a tree with arrows annotation:
Example of the interface with a split window:
