Publishers can now sell native and mobile video ads programmatically through Google's DoubleClick, the company said Friday.

The ads can be sold through either DoubleClick's open auctions or the private marketplaces run by publishers, and can appear in websites or in apps.

The system will soon enable buyers to purchase an ad to run across multiple kinds of screens in one shot as opposed to buying app and web inventory separately, Google said.

EBay was one of the first companies to use the programmatic capabilities.

"As a pioneer in the programmatic space, eBay recently rolled out its Native Mobile Programmatic solutions, which have revolutionized the way brands deliver their message to the right person, at the right time," Jonathan Bellack, director of product management at Google, wrote on the company's blog Friday. "Since the launch of its new native ad unit, eBay is seeing a 3.6x increase in ad engagement on average, with some campaigns delivering click-through rates up to 5%."

"We're focused on leveraging DoubleClick's technical footprint to bring scalability to our native mobile programmatic offering," said Brian Brownie, director of U.S. display operations and programmatic advertising at eBay, in the blog post. "Our success with desktop private marketplaces, backed by eBay insights, has unlocked massive client adoption and this next phase of mobile delivery is a continuation of the effort."

Programmatic interstitial video ads will also be available for apps on DoubleClick AdExchange.

"Video is key to driving brand impact in the moments that matter, no matter where they occur," Mr. Bellack said. "With these new immersive, full-screen video ads available programmatically, again in both the open auction and in private marketplaces, publishers can offer their advertising partners a new way to bring engaging brand experiences to users seamlessly, driving advertiser performance and growing publisher revenue."