Memory Word is a free educational app designed for Android users to enhance their English and Japanese vocabulary through an innovative lock screen study method. Users can select from various vocabulary themes including basic words, TOEIC, travel, and exam preparation, making it versatile for different learning needs. The app rewards users with cash for completing vocabulary quizzes, which can be exchanged for gift cards, adding an element of motivation to the learning process.

Key features of Memory Word include daily quizzes, sentence reading exercises, and a speaking function to practice pronunciation. Users can create personalized word lists, access listening modes for studying on the go, and participate in community discussions to share learning tips. The app also offers a unique roulette feature that guarantees daily rewards, making vocabulary study both fun and rewarding.