RETINA Simulation™ is the main and the most technological product of ESTD. It is developed during 4 years using the valuable numerical analysis and software development knowledge of developer team.  RETINA Simulation™ is a block oil and compositional, finite volume, unstructured based and parallel reservoir simulator that is built and optimized to be fast and stable specially, for large, complex and fractured heterogeneous reservoirs. It has been tested by numerous real carbonate fractured and non-fractured oilfields in Middle East area. Various companies officially certify its accuracy and stability.  The powerful and stable linear solver and preconditioner CPR-AMG based ILU0, fully integrated pre and post processors, and equipped with real time result visualization(plot and grid) and live update of the model are main features of RETINA Simulation™.