Venture-backed Gradient X has completed the six-month beta of its real-time bidding advertising platform for mobile devices and opened up to all marketers and brands.

The startup bills itself as the “most advanced” platform in mobile programmatic marketing, a form of digital marketing that lets advertisers bid in real time and target consumers across sites.

gradientx 730x484 Real time bidding mobile ad platform Gradient X emerges from beta

The gap between desktop and mobile ad rates has made the mobile space a frontier for advertising platforms. For its part, Gradient X claims to have achieved feature parity on mobile through “highly effective predictive bid and optimization algorithms, data segmentation and management, advanced targeting and unprecedented control, and transparency.”

During its beta phase, the startup built up a global network of 400 million unique mobile devices and over 50 billion mobile optimized impressions and worked with big-name brands such as Western Union, Jeep, Audi, Toyota, Motorola, HTC and Microsoft.

Gradient X has raised $3.75 million from a number of notable investors: Rincon Venture Partners, GRP Partners, CrossCut Ventures, Founder Collective, Siemer Ventures, Baroda Ventures, Double M Partners LP, Fred Krueger, Walter Kortschak, Mark Suster and Clark Landry. The company is run by advertising veterans who spent time at Adconion Direct, Rubicon Project and OpenX.

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