App Store Sales: Brain Hack, World Countries, XpenseTracker

Developers are continuing to offer apps at limited-time discounts or giving them away for free to boost their numbers. Arnold Kim, founder of MacRumors, created a great new way of looking for iPhone apps online called AppShopper.com, which was used to compile this list. Today's list includes TKO Marbles, TKO Numbers, TransMate, XpenseTracker, World Countries, American Dominoes and BrainHack.

• TKO Marbles - $0.99 -> Free
  TKO Marbles is FREE for a limited time only!
• TKO Numbers - $0.99 -> Free
  TKO Numbers is FREE for a limited time only!
• TransMate - $2.99 -> $1.99
  TransMate is now on sale -- $1.99!
• XpenseTracker - $12.99 -> $9.99
  *** SPECIAL PRICE THROUGH FRIDAY MIDNIGHT ***
  Now $9.99 US. Will return to $12.99 US on Saturday.
• World Countries - $2.99 -> $0.99
  *** INTRODUCTORY PRICE $0.99 ***
  World countries Fact Book with capitals and flags quiz games.
• American Dominoes - $1.99 -> $0.99
  HALF PRICE SALE - $1 - the lowest possible price in the AppStore. Classic, easy to learn, challenging, addicting and most of all - fun!
• BrainHack - $2.99 -> $0.99
  SALE! EXPERIENCE THE POWER OF IT FOR JUST $0.99 FOR A SHORT TIME!