The app description from app developers (Disclaimer English Only):
The Starfall ABCs FREE app is made possible by the member supporters of Starfall.com, a publicly supported nonprofit. The activities at Starfall.com motivate through exploration, positive reinforcement, and play.
Children delight as they see, hear, and interact with letters and sounds in words, sentences, and games. They learn to recognize letters while developing the skills they need to become confident readers. All children, especially English language learners, benefit.