The deal will allow Roku to provide marketers with software to plan, buy and manage their ad spend across TV and OTT providers.

While OTT accounts for 29 percent of TV viewing, it has only captured three percent of TV ad budgets. And advertisers spend an estimated $70 billion on traditional TV ads. This acquisition could help Roku, which has more than 30.5 million active accounts, get a bigger slice of the pie. That could be critical considering that Roku actually lost money in 2018.

Roku has faced criticism for allowing its Roku TVs to eavesdrop on your shows and for selling user data to advertisers. Unfortunately, that's fairly common, but with settings like "Limit Ad Tracking" it can be controlled a bit.

Roku expects to close the Dataxu deal in the fourth quarter of 2019.