HyperMagic app for iPhone and iPad

Hyper Magic estimates the probability of drawing a certain combination of cards given a number of drawn cards, deck size and amount of desired cards in the deck.
For instance, by default we show a deck of 60 cards from which 25 cards have been drawn. What is the probability of having in our hand one of four cards of a desired type (e.g., clubs, aces, lighting bolts...)? The answer is roughly 90%. What would be the probability that our very first card is the one we are seeking? Less than 10%, etc.
This is kind of information can be used to build balanced decks on games such as Magic the Gathering. For example, we can estimate the right number of lands to include on a deck, based on the amount of lands we need by a certain turn of the game.