Open TOPOJSON on Phone

TopoJSON stores topology-aware geographic shapes in JSON, often smaller than plain GeoJSON.

• Phone viewers usually show geographic data as dense raw text.
• A coordinate summary is often enough to confirm what the file contains.
• Large maps and full GIS editing are too heavy for a quick mobile preview.

OpenOnPhone is for quick local inspection. It does not replace the original professional app for editing, conversion, exact layout, formulas, measurements, security review, or full workflow features.

• application/octet-stream
• text/plain

• Choose the TOPOJSON file on the home page.
• OpenOnPhone shows a local geometry and coordinate summary.
• Use a GIS tool when you need map rendering, projection conversion, or editing.

• JSON.json
• CSV.csv
• Markdown.md
• Text.txt
• Log.log
• SVG.svg

What is a .topojson file?

TopoJSON stores topology-aware geographic shapes in JSON, often smaller than plain GeoJSON.

Can OpenOnPhone show a quick view for .topojson files on phone?

Yes. OpenOnPhone can show a quick local view for .topojson files in your browser.

What should I try next for .topojson files?

Choose the TOPOJSON file on the home page. OpenOnPhone shows a local geometry and coordinate summary. Use a GIS tool when you need map rendering, projection conversion, or editing.