System Requirements Document (SRD) for Lemon-App

1. Introduction

Welcome to the System Requirements Document (SRD) for Lemon-App, a location-based timer application designed to enhance safety during emergency scenarios. This document outlines the functional and non-functional requirements, design concepts, and technical specifications for the development of Lemon-App.

The app is tailored to meet the needs of users in Israel (IL), considering local contexts such as timezone (Israel Standard Time), currency (ILS), and emergency preparedness protocols. Lemon-App aims to provide users with a reliable tool to track the time left to reach a designated protected area during alarms, ensuring safety and peace of mind. Inspired by the clarity and authority of Home Front Command, the app emphasizes simplicity, calmness, and user-friendliness.

2. System Overview

Lemon-App is a mobile application that combines real-time location tracking with time management to assist users during emergency situations. The app allows users to:

1. Define a protected area as a location.
2. Start a timer during an alarm based on their current location.
3. Monitor the remaining time to reach safety.
4. Customize notifications with options for sound, vibration, or visual alerts.
5. Re-run specific functionalities for regeneration based on user-triggered actions.

The application will leverage GPS technology, intuitive user interfaces, and robust backend systems to deliver a seamless experience. It will also integrate with APIs for location services and emergency notifications, ensuring accurate and timely information. The design will prioritize clarity and calmness, avoiding stress-inducing elements while maintaining urgency where necessary.

3. Functional Requirements

User Stories:

• As a User, I should be able to set a protected area as a location.
• As a User, I should be able to start a timer during an alarm based on my current location.
• As a User, I should be able to track how much time I have left to reach the protected area.
• As a User, I should receive notifications when I am nearing the protected area or running out of time.
• As a User, I should be able to view my location on a map relative to the protected area.
• As a User, I should be able to customize the alarm settings (e.g., sound, vibration).
• As a User, I should be able to access historical data of past alarms and timers.
• As a User, I should be able to share my location and timer status with emergency contacts.
• As Admin, I should be able to pre-approve the application via an API supervisor.
• As a User, I should be able to selectively re-run specific functionalities to regenerate data or settings.
• As a User, I should be able to choose notification types (e.g., main-screen pop-ups or top-screen alerts).
• As a User, I should be able to enable or disable sound and vibration for notifications.
• As a User, I should be able to change the app language between Hebrew and English.

4. User Personas

Persona 1: Everyday User

• Description: Individuals who want to ensure their safety during emergencies, such as natural disasters or workplace safety drills.
• Goals: Quickly set a protected area and monitor time left during alarms.
• Pain Points: Lack of real-time location tracking and difficulty estimating time to safety.

Persona 2: Admin

• Description: Supervisors or emergency coordinators responsible for managing app functionality and approving API integrations.
• Goals: Ensure the app meets safety standards and integrates seamlessly with external systems.
• Pain Points: Complexity in managing API approvals and ensuring system reliability.

5. Visuals Colors and Theme

Color Palette:

• Background: #F3F8FC (Gentle Sky Blue)
• Surface: #E6EDF2 (Soft Glacier Gray)
• Text: #1A1D2E (Deep Midnight Blue)
• Accent: #FFD700 (Bright Lemon Yellow)
• Muted Tones: #A3A3A3 (Neutral Calm Gray)

Theme:

The Lemon-App will feature a calming yet authoritative aesthetic, inspired by Home Front Command. The colors are chosen to evoke trust, clarity, and focus during critical moments. The design will avoid stress-inducing elements, focusing instead on reassuring visuals and intuitive navigation.

6. Signature Design Concept

Concept: Emergency Pathway Visualization

The Lemon-App homepage will feature an Emergency Pathway Visualization that dynamically guides users toward their protected area in a clear and calm manner.

Key Features:

1. Dynamic Path Animation: A glowing pathway on the map shows the safest route to the protected area, updating in real-time based on the user's location.
2. Timer Integration: The pathway includes a countdown timer overlay, with visual cues like soft pulsing lights as time progresses.
3. Map Interface: Users can view their position relative to the protected area, with clear markers and directional arrows.
4. Micro-Interactions: Gentle vibrations and soothing sound effects provide reassuring feedback as users approach safety.
5. Color Transitions: The pathway transitions from blue (safe) to orange (alert) to red (urgent) based on the remaining time.
6. Motivational Messages: Encouraging text like "You're almost there!" or "Stay calm, keep moving!" appears at key moments.

This design ensures the app is visually striking, functional, and emotionally supportive, leaving a lasting impression on users.

7. Non-Functional Requirements

• Performance: The app must load within 2 seconds and handle up to 10,000 concurrent users.
• Scalability: Support future expansion to integrate additional safety features.
• Reliability: Ensure 99.9% uptime for critical services like location tracking and timer functionality.
• Security: Implement end-to-end encryption for user data and location information.
• Localization: Support Hebrew and English languages for users in Israel.
• User-Triggered Regeneration: Allow selective re-run of functionalities without impacting overall system performance.
• Customizable Notifications: Enable users to choose notification types, sounds, and vibration settings.

8. Tech Stack

Frontend:

• React Native for mobile app development.

Backend:

• Python with FastAPI for API development.

Database:

• MySQL for relational data storage (using Alembic for migrations).
• MongoDB for NoSQL data storage.

AI Models:

• GPT 5.4 for user-friendly responses.
• Google Nano Banana for image generation.

AI Tools:

• Litellm for LLM routing.
• Langchain for advanced AI workflows.

Orchestration:

• Docker and docker-compose for local development.
• Kubernetes for server-side orchestration.

9. Assumptions and Constraints

Assumptions:

• Users will have access to GPS-enabled devices.
• Emergency scenarios will involve predefined protected areas.
• The app will primarily target users in Israel.
• Users will prefer a calm and clear interface inspired by Home Front Command.

Constraints:

• Real-time location tracking may be affected by poor GPS signal.
• API supervisor approval is mandatory for app deployment.
• The app must comply with local data privacy regulations.
• Selective re-run functionality must not disrupt ongoing processes.

10. Glossary

• Protected Area: A designated safe location users aim to reach during emergencies.
• API Supervisor: An administrator responsible for approving API integrations.
• GPS: Global Positioning System used for location tracking.
• Timer: A countdown mechanism indicating time left to reach safety.
• Selective Re-Run: A user-triggered feature to regenerate specific functionalities or data.
• Localization: Support for multiple languages, such as Hebrew and English.
• Customizable Notifications: User-defined settings for alerts, including sound, vibration, and visual cues.