iTranslate

Four out of Five Stars
Free

iTranslate is the best translator app I have found. It has 52 languages, probably a lot that you will never use. It is great for travel to a different country or for translating something in a book. Here is how it works: enter your text in the box at the top, then choose the language you wrote it in. find the language you want with the other language selector and press translate.
It literally couldn't be easier. Nice app, I have it on my iPod.