Ilhas do Alfabeto (in English Alphabet Islands) is a digital game designed to support the literacy process (before, during and after), suitable for children as from 5 years old. The game incorporates all the necessary skills for the child to become literate: knowledge of letters, phonemic awareness, alphabetical principle, decoding and reading fluency. Ilhas do Alfabeto offers an adventure in literacy in 4 “islands”. “Letters’ Island” presents letters, develops knowledge of name and form of the letters, helps to learn alphabetical order and calligraphy. “Sounds’ Island” lead the student to identify and discriminate phonemes and graphemes. “Words’ Island” presents the relationship between phonemes and graphemes, exploring different skills (identifying, discriminating, isolating, joining, completing, forming simple words and phrases). “Texts’ Island” presents decodable texts in increasing complexity. The game has shown positive effect on improving literacy on RCT impact assessment.