Vocabulary-related main features:
1. Category: plenty at your fingertips
2. Quiz: over 20,000 words in 100 levels
3. Audible: listen to words, definitions and example sentences even with locked screen
4. Lesson: listening, speaking, writing and translation drills
5. Review: wrong answers, new words, example sentences
6. The rest: vocabulary counter,human pronunciation in US or UK accent and male or female voice, and optional bilingual layout
Character-related main features: similar to those of vocabulary