Where this utility varied from the others I found was that it came at the problem from the other direction, instead of entering your gear configuration and seeing what the TPI or pitch was you could enter your gears and the pitch or TPI and it then calculated the gears you needed, the position they should go in and even the error in the pitch if you were trying to cut imperial threads on a metric leadscrew.
I purchased one of the 63 tooth gears from arceurotrade hoping to cut imperial threads on my metric lathe and this utility proves that it can be done and the error in dimensions is less than with the standard gears.
So after looking at the source code and scratching my head for a while I thought the easiest way would be to use Appinventor and create an app that just displays the code in a Web viewer so you can use it off-line.
I reduced the number of gears available and moved some of the info around so it would better fit on a phone screen.
I've checked with the creator and he's happy with this so here are some links.
The source on Appinventor Community Gallery here
The APK file here