The Texas Hold Em Odds calculator will tell you your odds of having the best poker hand at any point in the game. It will also tell you your odds of making a better hand on the turn or river.
Unlike others, this one doesn't require you to know your opponents hand because they aren't going to show you in a real game.
Just a note about "Van's" comment. This app calculates odds after the flop and then again after the turn and after the river. Calculating pre-flop odds would be misleading since the odds would change so drastically after the flop.
Works great for WSOP, Full Tilt Poker, Poker Stars, World Series of Poker, fulltiltpoker.net, pokerstars.net, Zynga, World Poker Tour, Facebook poker, WPT, High Stakes Poker and any other live or online game.
1.0.4 New Icon
1.0.3 Fixed A,2,3,4,5 Straight Flush detection.
Improved app startup performance for low speed network connections.