SecondChance - Overdose Prevention App

App's Main Menu with Emergency "SOS" button and a secondary "Someone Else Needs Help" Button
When pressed, the "SOS" button starts countdown after which it calls 911 with users location
The App Informs the User when a Call has been placed, Placeholder number was used for demo/testing purposes
When the yellow button is pressed instructions for administrating NALAXONE are displayed
The menu has several
The
The app also has a map

Inspiration

Fentanyl and other opioids are a major public-health crisis in Canada, with thousands of lives lost each year. One of our team members has been personally affected by this tragedy, and we want to make it easier for people to get help and for bystanders to respond effectively. We built SecondChance because we believe everyone should have access to clear information, fast emergency support, and the resources they need to survive and recover.

What it does

SecondChance is a simple, minimal mobile app that helps people get emergency assistance, locate life-saving resources, and learn how to respond to an overdose. Key features: SOS (I need help NOW): A large red SOS button with a 5-second confirmation countdown to avoid accidental presses. After the countdown, the app can place an emergency call and (with user consent) relay a short, human-sounding message that the caller may be overdosing and include their location. Important: This is intended to assist in emergencies; real-world deployment would require coordination with emergency services, legal review, and robust safety testing, so our current implementation calls a group member for demonstration.

“Someone else needs help”: Step-by-step text instructions with helpful illustrations and a human-sounding audio guide for administering naloxone (Narcan®) and basic first aid for suspected opioid overdose.

Maps: Interactive maps showing nearby free naloxone distribution locations, safe injection services, and local mental-health and addiction resources. The map centers on the user’s current location and shows nearest sites.

Signs of overdose: Visual and textual descriptions of common overdose signs, accompanied by an audio narration.

Chatbot + AI assistant: A built-in chatbot with curated, pre-written answers to common questions (so essential guidance is available offline). For additional support, an online AI agent provides tailored responses and resource links when connectivity is available.

How we built it

For the app's Frontend, we used JavaScript (React Native) allowing us to build the app's interface and design it to visually appear and function the way it does.

For the app's Backend, we used Java (Spring Boot) in order to allow all the other apps, websites and services used to effectively communicate with the front end and provide the user a seamless, simple, and fast experience.

Additionally, we used Render (HTTP Cloud Hosting), for performing API calls, allowing the API calls and the overall hosting to be performed externally on the cloud, allowing for scalability beyond the demo laptop.

We also used Leaflets through APIs to provide the user with accurate, real time display of their current location as well as the closest safe injection sites, Narcan supply places and support resources.

We also heavily utilized ElevenLabs to create authentic, human sounding voices, allowing the 911 calls to transmit the information to the 911 operator in a legible yet effective way as well as be able to provide verbally say the instructions to the user in a time-sensitive or stressful setting without overwhiling them with information or the robotic tone.

Another major component of our project was the use of Gemini API, which allowed for the user to get real time advice, support and resources from an artificial intelligence chatbot while taking into account the urgent and sensitive nature of the topic.

The use of Twilio allowed the app to make phone calls from an online server directly to emergency first responder services, ensuring the user can get help at a click of a button regardless of their device, phone plan or other factors.

Finally, Google's Antigravity IDE made it possible to seemingly connect the backend, frontend, as well as github all in one place. Additionally, seamless integration of AI agents and being built with the use of AI in mind, made troubleshooting, use and connection of external API and AI sources a breath and a far simpler task, allowing our team to connect on what matters.

Challenges we ran into

One of the biggest challenges we have experienced during this project was learning, getting familiar and being able to take full advantage of all the extensive features offered by the AI tools we have never used before such as Google's Antigravity IDE. Re-learning ways to do the tasks previously done countless times but in a new, far better and more efficient way made the building process not only insightful and educational but also fun.

Another challenge we experienced was connecting all of our backend websites and services together with our frontend interface to provide a smooth, fast and seemingless experience for the user. Since our app heavily utilizes features from online software and AI models while also using the phones stored data, being able to connect all the services together while keeping the system easily scalable far beyond the demo laptop proved to be a tough yet solvable challenge.

Accomplishments that we're proud of

One of the biggest accomplishments we have made within the projects is successfully implementing the calling feature. With the app's main focus being providing people with an easy and fast way to get medical help in case of an overdose, being able to make 911 calls transmitting users location and information about their overdose with the press of a button, the app is able to perform its main function potentially saving lives.

Another core aspect of our app which we are very proud of is the successful implementation of ElevenLab's Ai voice allowing for the user to hear and receive information in a simple, logical and structured way in times of crises or emergencies from a human sounding voice, helping the user stay calm while effectively receiving instructions in both a visual and an auditory way. The use of the ai voice also makes it far easier for the app to contact and provide information to the emergency service operations.

Finally, implementing the app and location tracking info allows our app to really stand out. Always knowing where to get help or find a narcan makes helping and receiving help easy and personally tailed information.

What we learned

We expanded our skills in React Native (mobile UI, permission handling, and API integration) and in Java/Spring Boot (building REST APIs and proxying third-party calls). We also gained hands-on experience using AI tools and voice-synthesis APIs and learned practical lessons about safety, privacy, and responsible deployment of emergency features.

What's next for SecondChance - Overdose Prevention App

Our next yet largest goal would be to officially collaborate with Ontario's provincial government, police as well as emergency services to ensure the app is able to reliably call and request the required help for those in times of crises. And hopefully, this collaboration can extend nation wide, providing the help for all that need it throughout Canada.

Additionally, being able to collaborate with individual safe injection sites, addiction support resources, or even municipalities would allow our app to reach as many users as possible, not only further raising awareness of the opioid epidemic but also giving people the tools they need to provide and receive help.