I'd argue that a mobile phone is not an adequate platform for coding. The touchscreen and keyboard layouts make it difficult to type needed symbols, distracting from the problem at hand. Coding requires deep thought, but phones are optimized for moving around rather than sitting in one place and thinking. As such, use cases like maps, calendars, communication and alarms get priority. The reason people buy a phone is…
Of course smartphones are mainstream so most owners are users not potential developers.. unlike the late 70s/early 80's computer scene which grew out of the hobby electronics scene where the early users were much more technical. My first computer came as a kit - bag of components and a motherboard - had to get out the soldering iron to build it.