• 

  Stay Safe, Always

GuardBand — Safety Is Just a Tap Away

An NFC-powered personal safety solution that makes requesting help simpler, faster, and more accessible.

Inspiration

In an emergency, every second matters. But what happens when someone can't unlock their phone, make a call, or explain their situation?

We wanted to explore a simple idea: What if getting help could start with just a tap?

That's how GuardBand was born.

Our inspiration came from the need for an affordable and accessible personal safety solution, especially for individuals who may find themselves in situations where asking for help isn't easy.

Instead of relying entirely on a mobile application, we wanted to connect a physical wearable with a digital emergency response system, allowing both users and nearby bystanders to take action.

What it does

GuardBand is an NFC-enabled personal safety platform that combines a wearable NFC tag, a mobile application, and a web-based rescue experience.

When someone scans a GuardBand NFC tag using a compatible smartphone, they can access a dedicated rescue page without needing to install the mobile app.

The platform includes several key features:

• NFC-powered rescue access: A tap on the NFC tag opens a rescue webpage, helping bystanders access emergency assistance options.
• SOS activation: Users can trigger an emergency SOS through the mobile application.
• Audible siren: An alarm designed to attract attention during an emergency.
• Emergency contacts: Users can add and manage trusted contacts.
• Email notifications: Email-based communication supports the emergency notification workflow.
• Safety check-ins: Users can register their safety status through the application.
• Activity history: A centralized view of recent safety-related activity.
• Mobile dashboard: A simple interface bringing together SOS, contacts, check-ins, history, and profile management.

Our goal is to reduce the steps between recognizing an emergency and taking action.

How we built it

We built GuardBand by combining mobile development, web technologies, backend services, and NFC hardware.

Tech Stack

• React Native + Expo: Cross-platform mobile application
• React: Web-based rescue interface
• Node.js + TypeScript: Backend services and REST APIs
• Supabase: Authentication and database
• Render: Backend deployment
• NFC stickers: Physical wearable interaction through an encoded rescue URL
• GitHub: Version control and collaboration

We started by mapping out the core user journeys: triggering an SOS, managing emergency contacts, checking in, and allowing a bystander to access the rescue page through an NFC scan.

We then developed the mobile interface and backend services, integrating authentication, emergency-related features, and data storage.

In parallel, we worked on the rescue webpage, which could be accessed through a URL stored on an NFC sticker. This allowed us to connect a physical object to a digital safety experience without requiring specialized hardware.

Finally, we brought the different components together, tested the main workflows, and refined the experience for our demo.

Challenges we ran into

One of our biggest challenges was setting up SMS notifications for emergency alerts.

We originally planned to notify trusted contacts through text messages. However, integrating an SMS provider introduced additional verification requirements and configuration complexities, which became difficult to resolve within the hackathon timeframe.

Rather than spending too much time on one integration, we adapted our approach and moved toward email-based notifications to support emergency communication.

Another challenge was bringing together multiple components: the mobile app, backend APIs, database, and NFC rescue webpage. We encountered Expo compatibility issues, deployment errors, and integration challenges along the way.

Building everything within a short timeframe meant making quick decisions, prioritizing essential functionality, and troubleshooting as a team.

Ultimately, these challenges helped us focus on the core experience and make practical engineering trade-offs.

Accomplishments that we're proud of

We're especially proud that we were able to turn a simple NFC sticker into the foundation of a connected personal safety solution.

Some of our key accomplishments include:

• Developing a functional cross-platform mobile application with a dedicated safety dashboard.
• Building an NFC-powered rescue experience that connects a physical wearable to a webpage.
• Implementing SOS functionality with an audible alarm.
• Integrating authentication, backend APIs, and persistent data storage.
• Building emergency contact management, safety check-ins, and activity history features.
• Adapting our emergency communication approach from SMS to email.
• Bringing mobile, web, hardware, and backend technologies together within a hackathon.

What makes this particularly meaningful to us is that GuardBand addresses a real-world problem using technology that is already widely available.

We didn't need to invent new hardware. We explored how an inexpensive NFC tag and a smartphone could work together to create a more accessible emergency assistance experience.

What we learned

Building GuardBand gave us valuable experience beyond just writing code.

We learned how NFC technology can bridge physical and digital interactions, how to build and integrate cross-platform applications, and how to connect frontend experiences with backend services.

We also gained experience with authentication, API integration, cloud deployment, debugging, and collaborative development using Git.

One of our biggest takeaways was learning how to adapt when an original approach doesn't work out. Moving from SMS to email reminded us that good engineering is also about making practical decisions and finding alternative solutions.

Most importantly, we learned to think about technology from the user's perspective. In an emergency, simplicity and accessibility matter just as much as technical functionality.

What's next for GuardBand

We see GuardBand as the beginning of a broader personal safety platform, with several opportunities to expand its capabilities.

Here's what we'd love to explore next:

• Voice recognition and hands-free SOS: Enable users to activate an emergency alert using predefined voice commands or distress phrases, especially when they cannot physically access their phones.
• SMS emergency alerts: Extend our email-based communication workflow to support instant text notifications to trusted contacts.
• Live location sharing: Allow users to share their location with emergency contacts when they activate SOS.
• Automated missed check-in detection: Detect missed scheduled check-ins and trigger alerts to trusted contacts.
• AI-powered safety assistance: Explore context-aware emergency guidance and intelligent risk detection to support users in different situations.
• Enhanced NFC integration: Improve how wearables interact with the mobile app and rescue webpage.
• Expanded accessibility: Adapt GuardBand for seniors, people with disabilities, and individuals who may need additional assistance.
• Wearable improvements: Explore integrating NFC into wristbands, keychains, and other everyday accessories.

Our long-term vision is to make personal safety technology affordable, accessible, and easy to use, without relying on expensive hardware or complicated setup.

GuardBand started with one simple idea: when someone needs help, one tap should be enough to get things moving.

Built With

• nfc
• react
• react-native
• supabase