Procore - Procore is the world's most widely used construction project management software. Easy to use, mobile platform with unlimited user licenses.
FreeCAD - An open-source parametric 3D modeler
PlanGrid - The #1 construction app. Used by thousands of companies to save time, money, and ditch paper plans forever.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Corecon - Corecon offers integrated estimating, project management, and job costing for small to medium-sized construction companies.
Onshape - Onshape is the first full-cloud 3D CAD system. It runs in a web browser and on any mobile device.