In the original 1982 “Poltergeist,” evil spirits entered the world through televisions. Now imagine what would happen today in our world full of smartphones and tablets. Scared yet? If not, the first teaser trailer for Gil Kenan’s “Poltergeist” reboot will freak you out. The remake of Tobe Hooper’s 1982 horror classic — which spawned the notoriously cursed film series — stars Sam Rockwell and Rosemarie DeWitt. Be prepared to jump if you’re afraid of clowns and stay tuned for the debut trailer on Friday. “Poltergeist” opens in 3D on July 24.