Summary: App sales dropped to 15/day. After changing to free for the next 24 hours, it shot up to 55,000. Mainly due to tweets/reviews from people keeping track of free apps, etc.<p>Take away: Apps need some publicity to break into the market and making them free gives you some leverage. Which is not too surprising.<p>Letdown: According to the blog comments, the authors won't be sharing the results of the app sales when the price is raised to 0.99 after the 24 hour period =(. Something which most of us will be keen to find out.