SAP2000 is described as 'The SAP name has been synonymous with state-of-the-art analytical methods since its introduction over 30 years ago. SAP2000 follows in the same tradition featuring a very sophisticated, intuitive and versatile user interface powered by an unmatched analysis engine and design' and is an app. There are more than 50 alternatives to SAP2000 for Windows, Linux, Web-based and Mac. The best SAP2000 alternative is Estru3D, which is both free and Open Source. Other great apps like SAP2000 are Robot Structural Analysis Professional, Etabs, sas-civil and Abaqus Unified FEA.