The linked pdf also has a list of the top five most infected markets.
NQ Mobile offers their mobile security suite in both free and premium versions.
Despite warnings that too few people protect access to their mobile device with a PIN, doing so does not prevent authorized users from being tricked into downloading malware. See: The Con is Mightier than the Hack
That means mobile security services are going to be an important factor in keeping the purple bar at the far right of the picture as short as possible.