Yesterday at GDC we sat down with Brian Robbins of Riptide Games who took us through their latest release, Shadow Ranch [link] (with an “HD" version for iPad [link]), an iOS adaptation of Her Interactive’s highly popular Nancy Drew Adventure series.

In a departure from the PC and console originals, the iOS Nancy Drew mobile mystery takes the form of an interactive book that works much like one of the old Choose Your Own Adventure stories. The primary portion of the experience is reading the story presented, eight chapters full of illustrations and media-enhanced hyperlinks. The other part of the app consists of three different kinds of mini-games. The outcome of a variety of hidden object games, word games, and horse racing games determine the path of the story and bring achievements. Several sideline mimi-mysteries are also included.

Brian also showed us Mini Monster Smash! [App Store], the fruit borne of Riptide’s all-night coding frenzy at November’s 360iDev Game Jam. The goal of the game is to smash a cute little red monster with a flyswatter to get it to fly as far as you can. Along the way the monster will bounce off of trampolines, bombs or float in bubbles.

And, finally, we had a look at an upcoming title called My Pet Zombie, which is being developed jointly with Recharge Studios. It’s one for the virtual pet fan who also has a thing for zombies. The game puts a cute little zombie in a graveyard setting on your screen for you to love and nurture. It even dances. But don’t take care of it and it’s one more tombstone in the graveyard. The game also features social aspects, such as freinds’ zombies going on a date, etc.

Shadow Ranch and Mini Monster Smash recently went live in the App Store, and My Pet Zombie is expected in late April or early May as a freemium release.