An application providing functions to forecast oil and gas production with multiple methods (e.g., RTA, PBEUR, Pseudo PBEUR, and DCA), and functions to conduct production diagnostic analysis to diagnose well or nearby reservoir issues and to inverse reservoir parameters (e.g., porosity, permeability, hydraulic fracture length, hydraulic fracture conductivity), and data analysis functions to investigate the main factors impacts on the well performance and improve well design and field development plan.