u/PixelGust_Stef

I saw a post by someone volunteering to find lost pets saying they are having trouble with accurate location data and they were asking if people knew an easy way to go about it. I got the idea to build a free app that makes it very easy to do that.

The workflow is this:
I want location data (last known location of a lost pet, nice fishing spots, nice restaurants in an area etc.). I make a project in this app and I get a URL I can share. People who want to help can click on the link and presented with a map where they can place pins with some optional text and timestamp.

The OP decides how many pins are allowed per person and what is the area the pins are allowed to go in. The volunteers don't need an account and it is completely free.

One could use this to send their friends a map with locations as suggestions for travelling too.

What do you guys thing?
The app is at gridsparrow.com

Hey r/gis ,

I've been building a web app called PixelGust as a side project for the past few months and I'd really appreciate honest feedback from people who actually work with this kind of data daily.

What it does: You click a point on the map (or draw a polygon) and it returns a full environmental profile. Weather climatology (ERA5), GFS nowcast/forecast, elevation + slope + aspect (SRTM 250m COGs), land cover (ESA WorldCover), NDVI (live Sentinel-2 via STAC), evapotranspiration (MODIS), soil erosion risk (RUSLE), flood susceptibility (TWI), and population density.

Tech stack for the curious:

• No Google Earth Engine at runtime. Everything is either pre-computed COGs on GCS or streamed on-the-fly from open data (Element84 STAC for Sentinel-2, NOAA for GFS)
• Backend: FastAPI + xarray + rasterio
• Frontend: React + Leaflet
• Hosted on Cloud Run

What I'm trying to figure out:

• Is this actually useful to anyone? Or is it just a cool demo?
• What data layers are missing that would make this a daily-use tool for you?
• For polygon/region analysis. What would you actually need that you can't easily get from QGIS or GEE?
• Is the UI intuitive or confusing?

I'm not trying to sell anything here, the core features are free. I genuinely want to know if this solves a real problem or if I'm building in a vacuum.

Roast it if it deserves it. Thanks.