Pocket-lint is hearing from all manner of content providers and broadcasters that a massive focus for them at present is coming up with the correct way to present a second-screen experience. Many of their viewers and subscribers now watch TV, movies, etc, with mobile device in hand, ready to interact in ever more immersive ways.At the moment, that mainly means a flashed hashtag or two on screen that programmers expect you to attach to relevant tweets. Or a button you prod in order to vote or play along. Thankfully though, there are also those who get it spot on, like Warner Bros with its...Sherlock Holmes: A Game of Shadows Movie App\nFormat\niPad\nPrice\nFree\nWhere\niTunes\nAlthough the latest Sherlock Holmes Blu-ray (which comes out on 14 May) is not the first to sync with a companion application, allowing you to enjoy the film and bonus material on a second screen simultaneously, it is the first that puts the app at the forefront of the experience (in the UK at least - Warner's own Happy Feet Two featured similar in the US).In fact, as the studio's own executive director of Creative Services, Donnie Roach, told us, you could even consider the iPad loaded with the Sherlock Holmes: A Game of Shadows Movie App as your primary display and the TV playing the Blu-ray as the second screen.That's because, instead of playing the movie and having the app keep up with each scene - as with Monty Python: The Holy Book of Days - this specific application presents copious amounts of information like a content-rich eBook, and allows you to play specific clips and scenes on the big screen through tapping icons in the app. At all other times, the Blu-ray shows a holding screen, so as not to be distracting.That's not to say the iPad app is not a fully featured bundle of information in its own right. It has plenty of video within that doesn't need the Blu-ray to work.There are interviews with experts and cast members, including Stephen Fry who can be considered both. There are rendered animations that were used by the film's production team to visualise scenes before shooting. And there are bundles of scripts, storyboards and location maps. Plus, if you're not able to access the Blu-ray (and you won't be until Monday), even the triggers scattered about offer 10-second previews when not synced or connected to the internet.We also like the application not being dedicated solely to Guy Ritchie's sequel, but having an entire section focused on the Sherlock Holmes myths and author Sir Arthur Conan Doyle. This includes a timeline of events that explains the most important moments in the great detective's lifespan, and there are nods at other, older portrayals of the character in TV and film.The app also allows you to share information learnt through Facebook and Twitter, ensuring it ticks social media buttons. And each cast member has his or her own section, with a gallery of pictures that can be placed anywhere you like on screen, rotated and expanded like a virtual scrapbook.There's certainly plenty to like and do, even if you have no desire to buy the Blu-ray, but that'd be a shame as it becomes so much more if you do. You needn't even worry about having an internet connection in your home (or one that both the Blu-ray player and iPad are hooked up to at the same time) because you can also sync video playback through a code system that's included. It's more clunky and requires you to input three-digit numbers every time you want to see a clip, but it works and would allow someone on, say, a plane to get the full experience too.If we were to be honest, this is not an application you'll want to delve too much into if you haven't seen Sherlock Holmes: A Game of Shadows yet - it's a hornet's nest of spoilers - but it will definitely give you plenty of reason to revisit the disc long after you've watched the film itself.Sherlock Holmes: A Game of Shadows comes out on Blu-ray in the UK on Monday 14 May. The Triple Play edition comes with a DVD and an Ultraviolet copy included, and the disc features the best use of Maximum Movie Mode (a visual walkthrough the entire movie with Robert Downey Jr and masses of interactive bonuses) yet. The app is available through iTunes now.