YES is an Android application developed by Mobile TeleSystems JLLC that offers an easy and fun way to learn English. The app includes over 3000 words with images and audio, allowing users to translate from Russian to English and vice versa. Additionally, YES offers a personalized learning plan that includes answering interesting questions and participating in interactive language duels with other subscribers.

The app also features a convenient list of word cards that users can add to manually or from the dictionary. Furthermore, YES allows users to challenge their friends or compete with the leaderboard's top scorer. Overall, YES is a free education and reference app that provides a comprehensive and engaging way to improve English language skills.