Dr. Geo is described as 'A software to design & manipulate interactive geometric sketches. It helps kids to explore geometry. Distributed with its source code it is modify-me-ready' and is an app. There are four alternatives to Dr. Geo for a variety of platforms, including Windows, Linux, Web-based, Mac and Android apps. The best Dr. Geo alternative is GeoGebra, which is free. Other great apps like Dr. Geo are Winplot, CaRMetal and GeoGebra Discovery.
GeoGebra is free and multi-platform dynamic mathematics software for learning and teaching. It has received several educational software awards in Europe and the USA.
"Winplot is a free graphing utility that was written by Richard Parris, a math instructor at Phillips Exeter Academy in Exeter, New Hampshire. Sadly Richard passed away in 2012. After Richard's death the program was still available for a number of years on the Exeter...
Dynamic geometry software based on René Grothmann's Compass and Ruler (CaR) software from 1989.
GeoGebra Discovery is an experimental version of GeoGebra. It contains some bleeding edge features of GeoGebra that are under heavy development and therefore not intended for every day use yet, so they are not included in the official GeoGebra version.
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