Location-based marketing platform Placecast has raised $5 million in funding from Quatrex Capital, Onset Ventures and Voyager Capital. Placecast's platform uses proprietary algorithms that weave together location information and other data from audiences across the web, mobile, and email. Placecast then analyzes inventory, segments audiences and targets ads for maximum relevance for advertisers and publishers. Placecast manages all of a publisher's web and mobile inventory, as well as serves targeted ads and messages into outgoing emails.