I most always access AW from either my iPad Mini or my iPhone. I never have any issues, and it keeps me logged in (I checked the box for that) so I don't have to keep typing my password. I use safari on both devices.
I don't think it should matter, but if it did, I did this on both my old iPhone 3GS and my shiny new iPhone 5 as well (newer and old operating system) and saw no difference. Also, I am in the USA, but I still don't think that matters...maybe I am just lucky so far?
I enjoy AW whenever I can, but if I were stuck to a real computer, I would miss out on most of it for that (I do admit I would probably post more if I were on a real computer- sometimes I "finger type" a message on my phone and just delete it, since I am not sure what it really looks like or if I didn't look carefully enough for spelling error red squiggle reminders).
ETA: oh yes, and I have never had pop ups either. And- this was typed from my iPad Mini. The thought of mobile not working would be so sad- I have grown to depend on it.