QSim provide a platform for researchers to explore quantum computers that are difficult to obtain.
IISc has developed a realistic quantum computer simulator named dm-sim (based on Density Matrix Formalism). It simulates the behavior/execution of quantum circuits on noise affected realistic quantum computers. Learn more about the dm_simulator here.
The C-DAC team has provided a graphical interface over the dm simulator so that the researchers/user can easily conceptualize and create quantum circuits, generate and execute programs on the simulator, view the results and easily/dynamically make changes in program / parameters.