According to Bango, it’s been fairly impossible to get an accurate count of the number of unique visitors to a mobile Web site and track the efficacy of a mobile campaign with a single tool. Until the release this week of Bango Analytics 3.0.

With new “image tag” technology, Bango Analytics 3.0 provides site owners with what the company says are the two most sought-after metrics: the number of unique visitors and the conversion rates from their mobile marketing campaigns. To make this possible, the software now enables two ways to capture mobile metrics – link tracking for campaign analysis and page tracking for site analysis.

Implementing the new site analysis feature requires only placing a line of HTML code on each page to be tracked.

“No one but Bango has a mobile analytics service that provides an accurate unique visitor count,” Bango CEO Ray Anderson said of the new release. “Mobile Web site owners can now get a real picture of the value of their mobile Web site.”

Bango Analytics is a hosted service that’s free for up to 100,000 page visits per month.