ChemDoodle is described as 'If you are looking for a chemical sketcher or an alternative to your current chemical drawing application, there is no better choice than ChemDoodle. ChemDoodle works on all operating systems (both 32 and 64 bit), has one of the largest feature sets in the industry, has the most' and is an app in the education & reference category. There are nine alternatives to ChemDoodle for a variety of platforms, including Windows, Mac, Linux, Flathub and Flatpak apps. The best ChemDoodle alternative is Chemaxon Marvin, which is free. Other great apps like ChemDoodle are JChemPaint, ChemDraw, ACD/ChemSketch and ChemCanvas.
Because it has a wide toolbox to manipulate chemical structures, it's free and it's easy of use.