The site whould be PS Vita friendly.
 

I was wondeeing when or is it possible for the site to be mobile device friendly?

It would take a lot of coding to make it mobile friendly. It takes money to pay someone to rework the code and Mene doesn't make enough money to pay someone. Unless a user could figure out how to do it gratis, I doubt it will happen any time soon.

I just use my android phone to access mene and I have no problems ^.^

It might just be my service. I will try it at a wifi hotspot.

I find loading it in desktop mode on a good browser works just fine :)

I know the 3DS web browser isn't particularly great so it might be a limitation of the Vita's software.

I think your right. Maybe in the next update.