Interesting topic.
Phones and tablets use RISC-based ARM processors. Normal desktop and laptop computers use processors based on the x86 architecture. These are the ones that Intel and AMD make. So in order to produce a coin that is primarily mined using smartphones, you would need to find a way to avoid getting swamped by the superior hash power of x86 CPUs. I'm not sure if such a thing is possible.
Can anyone with some knowledge about mining algorithms and CPU architecture shed some light here?
Also, maybe set CPU usage so phone wont melt
This would need to be implemented too, of course.