AppsFlyer, a mobile advertising measurement platform has raised $20 million in Series B funding. The round was led by Fidelity Growth Partners Europe (FGPE), the venture and growth capital arm of Fidelity Worldwide Investment, focusing on high growth businesses, with participation from AppsFlyer’s existing investors, Magma Venture Partners and Pitango Venture Capital. With this funding, the company has raised $28 million to date, company officials said.

“We solve a major gap in the industry by providing mobile marketers the transparency they require so they know where their most valuable customers are coming from and where to get more of them. In Asia, which has 3 billion consumers, we are accelerating our growth and establishing greater presence across the region,” said Ronen Mense, AppsFlyer VP of APAC.

Market research firm eMarketer predicts that global mobile ad spend will hit $64 billion this year and reach $158 billion by 2018. Yet many advertisers remain cautious with the medium, largely due to an inability to measure the outcome of campaigns.