Do you crave more Portal 2 development insight? Enough to pay for it? Fret not: Portal 2 - The Final Hours is now available on Steam as well as iPad. It'll set you back £1.49/$2.00

The 15,000 word multimedia experience/interactive documentary/digital book was created by Geoff Keighley during Portal 2's development. Valve gave him "fly on the wall" access to their offices, resulting in a "gripping and dramatic story brought to life by exclusive photos, videos, interviews, interactive experiences, and other surprises."

Read on for the details and Craig's mini-review.

According to Steam, The Final hours of Portal 2 reveals:


That Portal 2 actually began as a prequel to the first game without portals or GLaDOS.

The Directed Design Experiments created after Half-Life 2: Episode 2, including video of a never-before-disclosed project, Two Bots, One Wrench.

How the story of Portal 2 evolved during development. See images and read surprising details.

How it worked with Jonathan Coulton to create "Want You Gone," the closing song to the game.

 
The interactive bits from the iPad version are also intact for the Steam release, albeit with less fingerprints/smudging. You'll get to:


Play with portals in an interactive diagram where you learn how portals work.

Muck about with a 360 degree panorama photos of the Valve office and design labs.

Listen to the songs that inspired the Portal 2 development team.

Hear Jonathan Coulton's Portal 2 song in various stages of development.

Puppet Wheatley in an interactive experience

Destroy Aperture Science by wiping your fingers over the screen (we assume you'll need a touch screen for that)

Interact with fans and voice your opinion via polls and a feedback form.

 
Craig was fiddling with the iPad version, back when it was hot on the App Store. He says that Keighley's "Access to Valve is remarkable, giving a glimpse into the surprising number of failures that goes into making their impeccable games. Buy it if you want to know everything about Portal 2." He also mentions that it took him about an hour and half to read the whole thing.