At Monday’s Game Developer’s Conference, Google unveiled a new ad format that will allow mobile users to stream samples of games that appear in their mobile search results.

The format, dubbed Trial Run Ads, gives users who search for a game on Google a “Try Now” option to sample an app before downloading it. The new ads, Google said, will give mobile users the ability to stream up to 10 minutes of play before prompting them to download the full app.

For now, the ads will only appear when smartphone users are connected to Wi-Fi, the company said.

Google said the ads will be rolled out in beta for selected U.S. advertisers in the next few weeks.

The new Trial Run Ads are an expansion of a concept first launched by Google in December. The initial version of the ads, however, only allowed for 60 seconds of streaming play.

Google also made several other ad announcements on Monday, including the introduction of Portrait Video Ads, which give users a full-screen video experience without having to shift their display horizontally, and targeted advertising for active gamers.

Google said more than 80 percent of video ads on its Google Display Network are viewed vertically despite being designed for landscape viewing, and said developers have seen improved click-through and conversion rates with Portrait Video.

Google said its Active User Targeting for Games allows advertisers to precisely target ads to mobile users who have who have spent more than 30 minutes playing games or who have played a Google Play Games game in the last 30 days.