About Saathi
Saathi (साथी, companion) shows the safety advice for one place on India's borders, coasts and frontier roads on a single screen: heat and cold, the river, the sea, official alerts and the road outlook. It keeps working without signal once it has been opened, and it keeps nothing about you except the place and language you choose.
Who it is for
- Patrol teams before they go out: how hot, how cold, whether a storm is likely, and the safer hours.
- People in border villages and fishing harbours: the river, the sea, the boundary and today's official alerts, in their own language.
- District officials and volunteers who brief others and need the same advice offline.
How it works without signal
- The first time you open Saathi with signal, your phone saves the app itself (about 0.3 MB) and the language files.
- When you choose a place, your phone saves only the files for that place, for example the heat forecast for that town and the river board. Choosing another place removes the old place's files.
- Each time you open Saathi it shows the saved advice at once and checks for newer data in the background. Refresh checks right away.
- Without signal, a banner says so and shows when the advice was saved. Every card shows when its data was issued, and warns when it is more than 36 hours old.
- You can add Saathi to your home screen. On Android, use Install Saathi in the app or Add to Home screen in the browser menu.
What it keeps on this phone
| Where | What | Why |
|---|---|---|
Browser storage, saathi.place | The id of the place you chose, for example dhubri | To open your place next time |
Browser storage, saathi.lang | Your language, for example bn | To keep your language |
Browser storage, saathi.theme | day or night, only if you press Day view | To keep the light Day view for bright sun, or the black default |
| Cache, app files | Pages, script, styles, icons, the list of places, emergency numbers, six language files | To open without signal |
| Cache, advisory files | The product files for your chosen place only | To show advice without signal |
What it never collects
- No location leaves the phone. Use my location reads the position once, finds the nearest place on the phone, and drops the position. Only the place id is kept.
- No account, no name, no phone number, no messages.
- No analytics, no tracking, no cookies and no advertising. Saathi sends nothing about you; it only downloads files.
- Like any website, the server that hosts Saathi sees each download: which file, when, and from which network address. The heat file is per town and the sea file per harbour, so those downloads show which place's files were fetched. The river, alert and road files are the same for every place.
- Latin letters use the Anek typeface, which the phone fetches once from Google Fonts (about 100 kB) and keeps with the app. Google sees that request, as for any page with web fonts, and nothing else. Hindi, Bengali, Assamese, Tamil and Gujarati use the phone's own fonts, so they need no download.
Where the advice comes from
Saathi does not make forecasts. It reads the public files that other Trinetra products publish and shows them as those products set them, with the product name and the time of the data on every card.
| Card | Product | Data behind it | Licence |
|---|---|---|---|
| Heat, cold and storms | Raksha | Open-Meteo forecast (best-match global models), CAMS air quality via Open-Meteo; WBGT heat categories from US Army TB MED 507, wind chill bands from Environment and Climate Change Canada, air bands from CPCB | CC BY 4.0 |
| River | Varuna | GloFAS river discharge from the Copernicus Emergency Management Service via the Open-Meteo Flood API, compared with the same point's 1997 to 2025 record; Open-Meteo weather for crossing hours | CC BY 4.0 |
| Sea | Matsya | Open-Meteo Marine waves and swell, Open-Meteo wind; boundaries from the treaty and award texts | CC BY 4.0; public legal texts |
| Official alerts | Sandesha | NDMA SACHET Common Alerting Protocol alerts, shown as issued, with a link to each official file | Public domain (stated in the feed) |
| Roads and passes | Marga | Open-Meteo forecast at points along public roads, NDMA SACHET alerts; road lines from OpenStreetMap | CC BY 4.0; ODbL |
| Places | Saathi | Trinetra's reference towns plus the towns, river points, harbours and road points the products cover, matched to districts | Trinetra; OpenStreetMap (ODbL) |
Levels (Normal, Watch, Warning, Danger) are each product's own. Official alert severity is the issuing authority's, shown as given. Methods: heat, rivers, fishers at sea, and the Saathi product page.
Emergency numbers
112 reaches police, fire and ambulance in every state and union territory. 1554 is the Indian Coast Guard's search and rescue number and is shown for coastal places. District (1077) and state (1070) disaster control room numbers vary by state, so Saathi lists them only for states whose disaster management authority publishes them: so far Assam, Tamil Nadu and Tripura. Every number links to its source and shows the date it was checked.
Languages
Saathi's own words are in English, Hindi, Bengali, Assamese, Tamil and Gujarati. The translations are drafts made by Trinetra and are marked as needing local review until district officials or community readers have checked them; if a translation differs from the English, the English is the reference. Alert texts, place names, river names and road notes come from the products and stay in the language they were published in. When an official alert carries text in your language, Saathi shows that text.
Limits
- Advisory only. Saathi is not an official warning. Follow IMD, CWC, INCOIS, NDMA, the Indian Coast Guard, the BRO and your district administration.
- Forecasts are model estimates for a town or the nearest model point. They miss local storms, flash floods on small streams and conditions at a particular field, bank or harbour mouth.
- Saved advice is only as new as the last time the phone had signal, and the products update a few times a day at most. Read the time on each card.
- Saathi covers the places its products cover, about 120 along the land borders, coasts and frontier roads. Places far from these get the nearest one, with the distance shown.
- Working without signal needs a browser that supports service workers (current Chrome on Android does). The first visit needs signal. Some browsers delete saved site data after weeks without use.
- Crossing hours and sea levels are not clearances to cross or to sail. Sea information is for awareness only and not for navigation.
Corrections
Write to contact@trinetra.in about a wrong number, a translation, or a place that should be listed.