The Mobile-SIG exists to improve the usability of Python on mobile devices, as mobile platforms have their own unique requirements and constraints.
There are two goals: To collaborate on porting CPython to mobile platforms and ensure that other Python implementations (i.e. Jython, IronPython) present much the same environment as CPython when running on mobile devices. To collaborate on the design of modules for mobile-centric features such as cameras, GPS, accelerometers, and other sensors to ensure cross-platform and cross-implementation compatibility.
The intent is to work on mobile-centric features in this group before proposal to python-dev, similar to how the distutils-sig operates.
Questions of how to use Python on mobile platforms currently are considered off-topic as there are many other existing places for those questions.