BabelDict is a free mobile translator that lets you perform translations between 17 different languages.
If you need to translate words between multiple languages then BabelDict might be a better option than going to buy a load of pocket dictionaries. The languages included are Czech, Dutch, English, Finnish, French, German, Greek, Hungarian, Italian, Polish, Portuguese, Romanian, Russian, Slovenian, Spanish, Swedish and Turkish.
The fact that you can mix and match languages and translate between any of them is great, although not all of them are completely comprehensive in terms of the vocabulary range (the Polish translations in particular weren't very reliable in my tests).
BabelDict is incredibly easy to use thanks to its stripped-down interface. You just use flick through the start and end languages using the directional buttons or the number pad then hit the search icon to start the translation. I will note at this point that BabelDict requires an Internet connection to perform translations, so use caution if you don't have a flat-rate data plan.
As a simple tool for performing translations across many languages, BabelDict makes for a handy alternative to a big pile of phrase books.