• by Tobi Elkin , Staff Writer @tobielkin, April 7, 2016

Reviewing eMarketer’s latest forecast for U.S. ad spend on programmatic media, it’s clear that mobile will be a key driver of the growth.

The research firm projects that U.S. programmatic digital display ad spending will reach $22.10 billion this year. And between 2016 and 2019, the last year in eMarketer’s forecast period, it projects mobile ad spending will nearly double, hitting $195.55 billion to account for 70.1% of digital ad spend--as well as more than one-quarter of total media ad spending globally.

The firm’s mobile projections are fairly aggressive, eMarketer senior analyst Lauren Fisher told RTBlog. Fisher notes that much mobile inventory is now purchased through programmatic channels. “A lot of the mobile app publishers that don’t have sales forces lean on programmatic. There are holdouts on programmatic for mobile, but the larger app publishers are starting to transition there. So we’re betting that programmatic will move through mobile,” she said.

She sees additional interest from mobile app pubs. Plus, the fact that Facebook and Google are heavily mobile media channels will greatly influences programmatic ad spending.

Fisher also sees the cross-device/cross-screen trend helping to accelerate spending on programmatic mobile. “If you’re going to buy across devices, chances are you’re going to execute those buys programmatically. It’s because of the technology you need to identify individuals across devices. A lot of tech is baked into the programmatic ecosystem,” according to Fisher.

For buyers, purchasing mobile inventory via programmatic channels can afford greater scale. But if you’re a smaller player and seeking cross-device solutions, that scale isn’t always there.