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
![Tongue](https://bitcointalk.org/Smileys/default/tongue.gif)
This would need to be implemented too, of course.