That's a good point! I also started programming on a graphing calculator. One difference is that calculators were very limited in what they could do. No camera

That's a good point! I also started programming on a graphing calculator. One difference is that calculators were very limited in what they could do. No camera, no GPS, no internet connection, the screen was monochrome and 80x80 or so pixels... so the very limited language and input methods worked fine. But on modern day devices, you want to build complex apps that can interact over the network, use the various sensors on the device, display rich media, manipulate video/images in real time, etc. The programming environment has to allow for all of this, which is the tricky part.