I think the User-Agent is the correct approach. By default MWG writes the user agent to the access.log. So to start I would look into the access.log and see if there are already some mobile devices, and how their user agents look like.
You could create lists of user agents which you can use to decide if a device is a mobile device or not. There is nothing pre-built so far, so you would need to setup some lists with regular expressions or wildcards to make the mobile/nopt mobile decisions.
Thanks Asabban, that´s what I was thinking about.
Just one more thing,
Is there a way to be able to watch these reports in the quick view on Web Reporter?
I mean, Can I edit the Web Reporter´s quick view to add some more customized reports?
Thanks very much
Probably. I am not familiar with Web Reporter and I don´t have an instance to test, so I can´t tell. Maybe someone else has already set up something similar.