'Master Vocabulary' is a highly productive vocabulary building app. It is loaded with 2000+ important and some of the most common English words. Words are grouped by category/topic. Featured categories include -

• Amount and Quantity
• Appearance
• Business
• Economy
• Education
• Emotion
• Environment
• Family and Relations
• Food and Drink
• Health and Healthcare
• Legal
• Money and Finance
• Person and Personality
• Politics
• Sound
• Technology
• Time
• Travel and Transportation
• Work and Profession

Features include -

• In-App translation to over 64 languages including Hindi Urdu French Spanish etc.
• Save/bookmark words
• Real-time Statistics
• Different types of test (MCQ Test Spelling Test Guess the Word Test)
• Add or edit your notes
• Words are grouped by category or topics

If your goal is to improve English vocabulary fast this is a great app.