What's the best Android app for practicing chess offline with a good tutorial system?

Chess by GamoVation is a strong candidate for offline practice and learning. The app's core strength lies in its accessible tutorial system, which breaks down fundamental concepts like piece movement, basic tactics, and checkmates. This makes it particularly useful for new players looking to understand the game without the pressure of online matches. For practice, the game offers multiple difficulty levels against a computer opponent, allowing users to progress at their own pace. A notable feature is the completely offline functionality, enabling practice during commutes or in areas with poor connectivity. However, reviews indicate a significant limitation at the higher 'Candidate' difficulty level, where the AI adopts an overly defensive, non-confrontational strategy that can lead to repetitive, unproductive stalemates. This flaw hampers the experience for intermediate players seeking a dynamic challenge. The ad implementation is generally reported as unobtrusive for a free app. For beginners needing a patient, guided introduction to chess rules and strategy, this app serves its purpose well, though its advanced gameplay leaves room for improvement.