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This is your source for reliable river gauge flow data, tailored for river enthusiasts, fishermen, and environmental researchers. This offline-first application provides near real-time river flow information through a straightforward interface.

GaugeWatcher aims to provide a simple, no-fluff experience for users to quickly access the river flow data they need.

The app supports over 9,000 gauges across the United States, with data sourced from the USGS in addition to gauges in British Columbia and Ontario Canada.

Download from the App Store

Technical Challenges

  • Offline First: The app is designed to work offline, so users can access the data they need even when they're out of cell service. Persisting data locally and syncing with the server, without exceeding usage limits, when possible was a key challenge.
  • Concurrent Data Fetching: The app fetches data from multiple sources concurrently, which can be a challenge to manage and keep in sync without blocking the main thread.
  • Source Data Formats: The USGS provides a simple REST API to fetch data while other sources provide CSVs. Parsing and normalizing the data from these sources, all while being mindful of the user's data plan and available storage space took some creative problem solving.

Stack / Frameworks