At Apple's Worldwide Developers Conference, my team shared what we have learned about how to design and build prototypes for better software interfaces. If you are interested in what I do, I hope you will take the time to watch some of these.
Three more coming at WWDC 2018!
Please say hello if you see me at a future WWDC! I usually help developers at the User Interface Lab. Some years we even have a Prototyping Lab.