AtNav
AtNav is a zero-trust, end-to-end encrypted location tracking and telemetry sharing application powered by the atPlatform. It enables users to share their real-time location with peers without relying on a centralized server. Coordinates are broadcasted directly between devices using ephemeral, highly secure symmetric keys that bypass standard server commit logs.
Architecture & Core Logic
Location coordinates are captured every 5 seconds using the device's GPS hardware. The TelemetryStreamer instantly packages these coordinates, encrypts them using the atSDK (AES-256), and fans them out directly to all authorized peers. This ensures that only the designated recipients can ever decrypt the location stream.
1. Ephemeral Notifications (TTL-N)
To prevent high-frequency coordinate data from bloating the atServer and ensure maximum privacy, all location broadcasts use a Time-To-Live (TTL-N) of exactly 60 seconds. This allows the notifications to completely bypass the standard server-side commit log, acting as a direct P2P data stream.
2. Local SQLite Storage (Drift)
When a peer receives coordinates via the TelemetryListener, they are stored strictly on the local device using a robust Drift SQLite database.
- ●Data Retention: Telemetry points are automatically evicted by a background loop once they exceed the 24-hour limit.
- ●Reactive UI: The database exposes reactive streams so the UI instantly updates map pins and trail polylines as new coordinates arrive.
Tech Stack & Tools Used
Core Technologies
- Flutter & Dart: Multi-platform UI framework allowing seamless deployment to Desktop and Mobile.
- Drift (SQLite): Strongly-typed local relational database for persistent coordinate storage.
- Geolocator: Hardware-level GPS integration for high-accuracy positioning.
Atsign Ecosystem
- at_client: PKAM authentication, key management, and SDK integration.
- NotificationService: Handles real-time WebSockets and end-to-end symmetric encryption.
- E2E Cryptography: Ensures absolute data privacy between peers without intermediaries.
Local Execution & Testing
AtNav is built on Flutter. To build and run the application locally on your desktop or mobile emulator, follow these steps:
# 1. Clone the repository and fetch packagesgit clone https://github.com/Neh2332/AtsignHackathon2026.git && cd AtsignHackathon2026flutter pub get# 2. Run the applicationflutter runNote: You must provide your own .atKeys file to authenticate your atSign on first launch.