Vroom Vroom. Beep Beep. Based on the popular and award-winning board books created by Priddy Books, this interactive first-word app entertains babies and toddlers as they discover the trucks inside. From bulldozers to fire trucks, children learn each truck’s name – and the noise that they make, too. There are questions inside, and little fingers will enjoy pushing back the sliding doors to reveal pictures of the answers. Adding to the fun is narrator William Dufris, who is also the voice of Bob the Builder.