The app is beautiful and well-implemented for the most part. I am a pediatric cardiology fellow, and I think this app is very useful for explaining cardiac anatomy to patients. However, just as another reviewer has already mentioned, when you run the animation of the cardiac cycle, the atria and ventricles contract at the same time. This needs to be addressed. Also, this would be an utter home run if you increased the level of detail of the anatomy to the level of medical professionals. A cardiologist better know the anatomy to a level far greater than this app illustrates. As a pediatric cardiologist in training, my dream would be for you to offer models of hearts demonstrating the wide array of congenital heart lesions.