EXCLUSIVE: The partnership represents a slight change of course for movie theaters that have been trying so hard to persuade people to put their phones away. Venues that receive their pre-movie commercials from Screenvision soon will encourage patrons to take out their phones and use the Shazam app to help them take advantage of advertiser offers. The companies plan to formally announce the partnership today at Screenvision’s first-ever upfront presentation, although a campaign involving the HTC 1 smartphone began April 12. Screenvision will run 15-second reminders urging moviegoers to take out their phones while the ads run; the Shazam app automatically identifies the ad that’s playing. At that point, companies could transmit to smartphones opportunities to enter contests, buy something, receive additional information or samples, or watch the ad again. The No. 2 movie ad sales company says the arrangement gives it a leg up on industry leader National CineMedia.