Good news for all mobile device owners (including Nook), the wildly popular app game, The Mystery of the Crystal Portal, is available for free until April 1.

Crystal Portal, from G5 Entertainment, is story-driven, casual game that leads players through beautiful scenes where you have to find hidden objects and solve puzzles.

Here is the trailer.

The game has been in Top 10 charts of the leading casual game portals and ranks among  the Top 10 grossing iPad games in 61 countries. Crystal Port has been available for free to iOS, Mac, Google Play and Kindle Fire users since Monday and as of yesterday (March 27), Nook owners were invited to check it out for free also.

This free special ends on April 1 so check it out now by visiting your mobile device’s app store.

For more app news and goodies, follow me on Twitter, @JeffMMcKinney