Debugging Ionic apps can be challenging due to the differences in behavior between a web browser and a native mobile app, requiring proficiency in various debugging tools and techniques. Simon Grimm, an Ionic insider, provides a comprehensive guide to debugging Ionic applications, focusing on browser-based tools like Chrome and Safari for remote debugging on iOS and Android. Key areas include inspecting API calls through browser debugging tools to resolve issues such as CORS errors, accessing and manipulating stored data via Ionic Storage or Capacitor Storage, and dealing with SQLite databases on both iOS and Android platforms. The guide also covers accessing device files, offering methods to extract app containers or use tools like Android Studio's Device File Explorer for file inspection. By mastering these tools and methods, developers can enhance their problem-solving skills and confidence in developing Ionic apps.