We would love to support iPad/iPhone/Android. But, it's not going to happen with Eschalon. The language used to make the game simply doesn't have the proper libraries needed to port the game to those platforms.
However, Book III is the final game using this engine. The new game which we are scheduled to begin production on after Book III is something completely new, with a brand new engine that will support those platforms.
I'm excited for his future projects going on the mobile platforms.