By Diane Bartz

WASHINGTON The founder of Branch Metrics, which developed a method of searching within smartphone apps, told a U.S. antitrust trial on Wednesday how his company struggled to integrate with devices because of steps Google took to block them.

The testimony came during the third week of a more than two-month trial in which the U.S. Justice Department is seeking to show that Alphabet's Google abused its monopoly of search and some search advertising. Google has said that its business practices were legal.

Google is accused of paying $10 billion a year based on "revenue share agreements" to smartphone makers, wireless carriers and others who agree to make its software the default and maintain its monopoly in search.

Alexander Austin, a former chief executive of Branch Metrics, said in meetings with Samsung, the Android phone maker was worried Branch's tools would cause conflict with Google.

Austin said he would be contacted by Samsung during a launch in 2019 and told, "Oh, we need to cut this functionality because Google says it's, like, in conflict or there's a risk to the contract."

Specifically, Branch had to make sure that its searches remained within apps and never linked to the web.

The government also called Anna Kartasheva, a Google executive, to ask her about emails that appeared to show Google was concerned about the presence of Branch Metrics software on smartphones.

(Reporting by Diane Bartz; Editing by Josie Kao)