From Joel Epstein:
This-to-That is an addicting word puzzle game. The goal is to create chains of words, with each word in the chain having exactly one letter different from the words above or below it.The game has three levels of difficulty. With a large internal dictionary and new puzzles generated on the fly, it is unlikely you'll ever see the same puzzle twice.Unlike many similar apps, this one allows you to solve the puzzles from either one direction or another.Each level has its own best score and you can post your progress on either Twitter or Facebook.To play, simply choose a level and then begin entering letters in the grid. To solve a puzzle, each line of the grid must consist of a valid word that has not already been used. All puzzles can be solved in ten steps and if you're stumped, you can resign to see the solution. It is possible, however, to create shorter solutions, and the app will automatically recognize shorter valid solutions.With no ads or in-app purchases, This-to-That offers an unlimited, uninterrupted, and unbelievable word play experience. Enjoy!