Knowledge is your best weapon in the endless war against mana screw. And the Manalyzer can give you that knowledge.

Just enter the number of cards in your deck and the number of mana. The Manalyzer analyzes this information to tell you when you are likely to draw the mana you need.

Almost as bad as too little mana is too much. And the Manalyzer can also tell you the odds of mana flood.

But wait, there's more! The Manalyzer will also tell you how likely it is you will need to take a mulligan.

Thinking of running 6 Forests in your sealed deck? By picking the parameters correctly, you can get the Manalyzer to tell you how likely it is you will have a forest in time to drop that big, nasty creature, so it can go over and bash your opponent.

Source: http://itunes.apple.com/us/app/manalyzer-for-magic-gathering/id380208124?mt=8