Company Duong Nguyen created these great apps:
Learn English by Conversation, English Speak and Vocabulary, Learning English with American Voice, Chat to learn English, English Pronunciation with Yobimi, Duolearn - Let's Learn English by Conversation, English Course for Beginner, Duolinsten: Learn English by Learning Conversation, Audio Books from Librivox, English Pronunciation Practice, Learn English Speaking - VOA, SearchWord: Find Word & Quotes, Gutenberg Ebook Reader, English Listening with Teddy, QRit! Barcode & QR Code Reader, and others..
