Ionic and Stamplay together provide a streamlined approach to developing cross-platform mobile applications by combining modern web technologies with scalable, maintainable backend solutions. Ionic offers a framework for building multi-platform mobile apps, while Stamplay serves as a Backend as a Service (BaaS) that allows developers to integrate third-party APIs through a web-based GUI, eliminating the need for extensive coding. The guide includes a starter kit to create a cross-platform to-do app, featuring user registration and task management functionalities, leveraging Stamplay's API for user accounts and task data handling. The setup process involves cloning a GitHub repository, installing necessary tools and dependencies, and configuring both the Ionic framework and Stamplay services. The application allows users to register, log in, create, update, delete, and manage tasks, with features to mark tasks as complete or incomplete, all without needing to write backend code. With these tools, developers can focus on the app's unique aspects and user experience, rather than backend complexities.