If you been browsing SD , might of caught something from there. A fake flash installer popped up on their site (which I knew it wasn't legit since I know my settings for updates) when I looked at a thread and I really don't visit that website. Might want to try to refresh/reinstall your browser and see if it still happens. I also had several logins hacked from other sites in the last 2-3 weeks, so really no telling what is going on.
edit - guess I missed the fact that you were browsing mobile, what kind of phone and version OS is it running?
That is why I asked in another thread about being able to see the last IP's that were used on our accounts, just to see if someone else accesses my login here (I really don't need to see them, just as long as I know the same IP's I login as are the only ones being logged).