1. Project Overview: Clearly describe the web app, its purpose, target audience, and user personas.

2. Goals and Objectives: Define specific, measurable goals and objectives.

3. Scope and Features: Provide a detailed list of features and functionalities, and describe the approach to responsive design.

4. Technology Stack: Specify programming languages, frameworks, and tools, considering responsive design frameworks like Bootstrap or Foundation.

5. UI/UX Design: Present wireframes, mockups, or design prototypes, and address accessibility and usability best practices.

6. Development Plan: Outline a clear timeline, milestones, resource allocation, and team responsibilities.

7. Testing and Quality Assurance: Define strategies for testing and implementing quality assurance measures.