How it works: Once you press the play button on the app’s opening screen, simply look at the interactive pages of your Ultimate Dinosaur Encyclopedia book through the app. Look out for pages with interactive boxes with the camera icon, marked 'SCAN THIS PAGE'. If you don’t already have the book, tap the play button on the app's opening screen and wait for 20 seconds to get a link to a retail page outside the app where the book can be purchased. This free app is available to anyone with a compatible iPhone or iPad running iOS 11.3 and above: iPhone SE and above and iPad 5th Gen. and above.