There's a Psychrometric Calculator iPhone App for that
Phoenix Restoration Equipment announces the release of its new, free iPhone application that will instantly calculate the psychometric data essential to restoration professionals. The user simply selects the grains or dew point screen, and then enters the temperature and relative humidity conditions for the inlet and outlet.
The “Grains” screen displays the grains of each condition and the grain depression. By entering the airflow rate in CFM, the calculator also provides the pints/day or lbs/hour water removal rates. The “Dew Point Screen” displays the dew point of the conditions and the moisture load in pints/day or lbs/hour based on airflow. The temperature input range is 0° to 150° F or -18° to 66° C; relative humidity 1-100%; and airflow up to 5000 CFM.