I travel to Germany 7-8 times per year. While many Germans speak some English, its easy to get in a situation where you cant depend on it. Yes its expensive, but it is also the best I have found so far. This is great on several fronts:
Comprehensive - I find almost everything I need covered (so paying the cost is well worth it when you might be stuck)
Easy to use - interface pretty intuitive. Before I had little books with limited words, and not always convenient to carry a big enough book to do any good. This is like a great big dictionary.
Pronounciation guide - the spoken version is terrific, since my English way of pronouncing is often far off the mark
Off line usage - I find I have to turn off internet access when in Germany because of cost, but this app works just fine regardless.
So its a must have. I hestitated because of the price, but have not regretted it at all.
AZDale about Wörterbuch Englisch PONS