Coded Crosswords for Pocket PCs - description from Softdepia.com:
In Coded Crosswords a standard crossword grid is filled with numbers ranging from 1 to 26, each representing a letter of the alphabet. The object is to substitute letters for the numbers so that the crossword is correctly filled in with real words.
Features: Support for the ARM, MIPS and SH3 processors; Complete setup and uninstall programs; Help file.
Coded Crosswords for Pocket PCs is a "Free to try" program. You can download and try it for an evaluation period.