Q: Whoa,  $2.99 is expensive!  Why are you charging so much?
A: On Amazon I see books of puzzles for more than $3.  Those books have at most a few hundred puzzles.  This Sudoku game will generate hundreds of thousands of unique puzzles.  There is always this answer too: The Oatmeal (read it for a good laugh, even if you are not convinced).

Q: How are you generating the puzzles?
A: I'm using an algorithm called "Dancing Links".  The puzzles are generated right in your browser.

Q: How did you implement that?
A: I used an excellent application framework called Sproutcore.

Q: Are you going to add new features?
A: I hope to, for sure.  I am always looking for constructive feedback so I can improve the sudoku playing experience.

Q: Will I have to pay for new features?
A:  I don't plan on double charging my customers.   If I add significantly complex behavior, like sending puzzles to friends, forming groups, social networking integration, I might raise the price, but if you bought it you won't have to worry.