A microflow does not know if it's called from a mobile client, web client, another microflow or some java action.
Basically you should try to detach your user interface functionality from your business logic. So a microflow handling some logic would not also deal with opening forms, but gets called by both the mobile and web microflow. This means you'd only have to recreate very small parts of flows. This is a very common design pattern called Model-View-Controller (a very brief summary can be found at http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller)