Secret Files: Tunguska came out on PC, Nintendo Wii, and DS between 2006 and 2010. Four years on and it's time for smartphones to get a version, and you'll be pleased to know that it's a pretty decent port, from what we've seen so far.
As reported in my hands-on video below, the touchscreen interface is used intelligently, the graphics are high fidelity, and the voice acting is crisp (if a little hammy).
There's 12 hours of gameplay in this premium release, and the story is loosely based on real-world events - revolving as they do around the massive explosion that occurred in the Tunguska region in 1908 (click here to fall down a Wikipedia rabbit hole), with a bit of suspense and intrigue thrown in there for good measure.
I didn't want to ruin the whole story for you, so here's a quick hands-on that covers the basics of everything you need to know about Secret Files: Tunguska.