gCADPlus is software developed by two Australians - one a scientist and one an engineer. Ten years ago due to our interest in CAD, we were asked teach landscape students in a local college to use AutoCAD and produce landscape plans. We found it difficult to help them develop CAD plans, primarily because AutoCAD is general purpose CAD software and not aligned with the landscape design and horticulture disciplines. To remedy that, as a fun project, we developed gCADPlus aiming to target landscape disciplines and make it high quality, but affordable.
Neither of us receives any funds from sales. Every cent earned goes to pay independent programmers to improve to the software. We have been able to keep the cost low and do not believe in charging an annual fee. Over the past 5 years we have delivered 30 + upgrades incorporating suggestions for improvements from our users. (see: http://www.plus.designcad.com.au/?q=node/71)