Czech Dictionary is a bidirectional dictionary. You can search both Czech & English words only by changing keyboard. This dictionary has a big database for English and Czech words. Along with the dictionary there are vocabulary builder games.

Best dictionary for students, teachers, travelers and for all people who want to learn English/Czech.

Core Features:
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→ 47,341 English words & Czech explanations (Upgradable to 65,638 English words)
→ 45,204 Czech words & English explanations (Upgradable to 67,806 Czech words)
→ Translator for long sentence
→ Online Pronunciation for English & Czech text
→ Offline Pronunciation for English text only
→ Wiktionary
→ Customized font change
→ Universal & Retina Display
→ Fast Searching
→ Bookmark List
→ Offline dictionary (internet is not required)

Translator Features
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→ Long sentence translation
→ Translation Copy Service
→ Translation Bookmark
→ Translated Email Service
→ Translated SMS Service
→ Translated Status in Facebook
→ Translated Status in Twitter
→ Translated Status in Linkedin

Vocabulary Features
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→ Word of the day with Notification
→ Flash card
→ Multiple Choice
→ Guess Word
→ Random Words
→ In game sounds
→ Achievements and Leaderboard for vocabulary scores

If you need ultimate word database, free pronunciation for English Text with no advertise then buy pro version.

Pro version named "Czech Dictionary"
http://itunes.apple.com/us/app/czech-dictionary/id402654012?mt=8