There is no difference. The full version is achieved by unlocking the trial version. While we know that both Palm OS and Windows Mobile have continued to be enhanced since our PDA games were released, there are no plans to update any of our PDA games. We do apologize that those games have not kept pace with the newer technologies, but we no longer have programming staff for those platforms. We have since moved to producing games for desktop computers, specifically for the Windows and Mac OS platforms.