popups

im normally quite careful with regards to my laptops and pcs and look after them quite well but somehow i had a lapse in judgment and downloaded a file i was linked to from this forum a while ago, cant mind what it was but its still haunting me. ive ran virus and malware scans,system fix scans...

For a few weeks now this pop up has randomly appeared when I have been on the internet using either the Chrome or Boat browsers on my Samsung S2 tablet and it's driving me nuts. The bottom left corner provides short cuts to recent apps and the top half is some random advert. Does anyone know how...