Although I don't have a specific app or website I would recommend using 3d simulations of human anatomy and physiology in pediatrics there are plenty out their only issue is that they cost money but they can prove very helpful and for me personally, I memorize a lot of my research by taking notes that I find useful or important and to read or go over them every day or as needed its Basically like a flashcard but besides that, there is a lot of useful sources out their to find and I always recommend books as well.