The key stages include concept ideation, prototyping, development (coding), testing, polishing (UI/UX design), and finally, deployment to app stores.Popular languages include C#, C++, and JavaScript (for web-based games). Game engines like Unity and Unreal Engine support these languages for cross-platform development.Essential features include intuitive controls, engaging gameplay mechanics, high-quality graphics and audio, social integration (leaderboards, multiplayer), and monetization options (ads, in-app purchases).