I have an idea for an app that a friend of mine has implemented in CSS: http://mathenchant.org/chipchip/ I’d be interested in people’s comments. Is it fun to play? Are the directions clear? I’m aware of glitches in the implementation (some of which are browser-specific or platform-specific), and do let me know about them, but those are of secondary interest; what I really want is ideas for making the app more fun, and (from those of you with some relevant experience) a sense of whether the game has commercial potential. The page runs on laptops and smartphones. If the boundaries between tiles aren't clear, try a different browser (and let me know about the issue). ChipChip started out as a math game, but James Tanton pointed out that there’s a much bigger market for anagram-syle word-games. So you can play in either Number Mode (the goal is to sort the numbered tiles into ascending order) or Word Mode (the goal is to spell a word). I specifically chose words with no repeated letters; do you think it would be more fun if I dropped this constraint? Jim Propp