1. Who operates Transit Hunter
Transit Hunter is an app and website that works out where and when a spacecraft such as the International Space Station will cross in front of the Sun or the Moon as seen from the ground near you, and tells you whether the trip is worth making.
It is operated by Embarc Information Technology Private Limited (“Embarc”, “we”, “us”), a company incorporated in India. Embarc is responsible for the information described in this policy. Our full contact details are in section 20.
This policy covers the Transit Hunter Android application
(com.transithunter.app), the Transit Hunter web app, and this
website.
2. Information we collect
Information you give us
| What | When | Why |
|---|---|---|
| Email address | Only if you sign in by email | To send you a sign-in code and to identify your account across devices |
| Saved places — an approximate location and the name you give it, such as “home” or “the farm” | When you save a place | So alerts can tell you when a transit is within reach of it |
| Alert settings — how far you will travel, minimum quality, quiet hours, which satellites and targets interest you | When you create or edit a watch | To decide which transits are worth interrupting you for |
| Equipment details — camera and lens or telescope specifications | If you add equipment | To calculate framing and resolution for your own kit |
Time zone — your device's time zone name, such as Asia/Kolkata |
When an account is created | To show event times correctly and to respect quiet hours |
Information created by using the service
- An account identifier, which is a randomly generated value. It is not derived from you, your device, or your email address.
- A session token that keeps you signed in. We store only a one-way SHA-256 hash of it, never the token itself.
- A record of the alerts we have sent you, and of transits matched to your watches.
- A count of searches per day against your account, used only to apply the free plan's daily allowance.
Information your device sends automatically
Like any internet service, our servers receive your IP address and basic request information when the app or website contacts us. See section 7.
3. Location information
Approximate location only
The Android app requests approximate location
(ACCESS_COARSE_LOCATION) and nothing more precise. It does not
request ACCESS_FINE_LOCATION. This is why Android's own
permission dialog asks whether to allow Transit Hunter to access this device's
approximate location, and why Android does not offer you a precise option — the
app never asked for one.
A transit is visible from a corridor a few kilometres wide, so approximate location is genuinely enough for the product to work, and precise location would be more than it needs.
Never in the background
Location is only ever read while you are using the app, and only when you ask it to find you. The app requests no background location permission, runs no background location service, and does not track your movements.
You can decline the location permission entirely and still use everything: typing a place name works just as well as tapping “use my location”.
Searches run on your device
The orbital calculation engine is bundled inside the app. When you search for transits, the computation happens on your device using public orbital data, and the coordinates you searched from are not sent to us.
What does leave your device
| When you… | What leaves your device | Who receives it |
|---|---|---|
| Run a transit search | Nothing. Your coordinates stay on the device | — |
| Search for a place by name | The text you typed — never your position | OpenStreetMap Nominatim |
| Look at the map | Requests for the map tiles covering the area on screen | OpenFreeMap |
| Save a place | Coordinates rounded to three decimal places (about 110 m) and a coarse location code accurate to about ±2.4 km, plus the label you chose | Us |
| See the weather for a transit | The observation point's coordinates, coarsened — a public astronomical location derived from orbital mechanics, not where you are | Open-Meteo |
| Tap “navigate” | The destination is handed to your chosen maps app. We do not supply a starting point | Your maps app |
Your device also stores the location you currently search from locally, in the app's own storage on your device, so it is there next time. That copy is not sent to us and is removed when you sign out or delete your account.
4. Accounts and signing in
You can use Transit Hunter without giving us an email address. Your first session creates an anonymous account with a randomly generated identifier, and you can search, save a place and set up alerts with it.
If you want your data on more than one device, you can sign in with your email address. We email you a single-use sign-in code that expires after 15 minutes. There is no password to choose, remember or lose. Requests for codes are rate-limited.
Sign-in codes are stored as one-way hashes and are deleted after use or expiry. When you sign in, the data from your anonymous session is carried across to your account.
Transit Hunter does not currently offer sign-in with Google, Apple or any other social account, and does not read your device's contacts or accounts.
5. Subscriptions and payments
Transit Hunter is free to use. An optional paid plan, Transit Hunter Plus, is sold in the Android app through Google Play Billing.
What our server receives and stores
- A purchase token and a product identifier issued by Google Play.
- A one-way SHA-256 hash of your Transit Hunter account identifier, which is attached to the purchase so it can be matched to the right account. Your raw account identifier is not sent to Google.
- The subscription status Google reports — active, cancelled, paused, expired or in grace — along with the plan, the billing period, and renewal and expiry dates.
- A record of the billing events Google sends us, kept so that a payment problem or a dispute can be reconciled.
How verification works
When you buy or restore a subscription, the app passes the purchase token to our server. The server asks Google directly whether that purchase is genuine and current, and takes the answer from Google rather than from the app. Nothing on your device can grant itself a paid plan. Google also notifies our server when a subscription renews, is cancelled or lapses, so that your access matches what you have actually paid for.
You manage, change or cancel a subscription in the Google Play Store, not in Transit Hunter.
6. Push notifications
If you set up a watch on a saved place and grant the notification permission, Transit Hunter can alert you when a transit worth photographing is coming up, when a prediction has moved materially, or when the cloud forecast for an event you were told about has changed.
These alerts are the product, not advertising. We do not send marketing, promotional or advertising notifications, and notifications are never used to deliver ads.
What is involved
- On Android, a registration token is issued by Google's Firebase Cloud Messaging and stored by us so we know where to deliver your alerts. In a browser, the equivalent is a Web Push subscription.
- Alert text is delivered through Google's push infrastructure. The text of an alert can include the name you gave a saved place and how far the observation point is from it — for example, “7.8 km from the farm” — together with the satellite, the time and a quality score. Because the alert passes through Google's push service, Google is technically capable of seeing that text in transit.
- Your saved coordinates and coarse location code are not included in a notification.
You can turn notifications off at any time in your device settings or by removing your watches. Signing out removes that device's push registration from your account.
7. Server logs and security data
When the app or website makes a request to our servers, the servers receive and log your IP address along with the request method, path and timing, in the ordinary way that any internet service does.
We use this for two purposes only:
- Rate limiting and abuse prevention, so that one caller cannot overwhelm the service for everyone else.
- Diagnosing faults and keeping the service running.
Your IP address is not stored alongside your account record, is not used to determine or infer your location within the product, and is not used for advertising or profiling. We deliberately avoid logging request contents that would contain coordinates.
Transit Hunter does not use a crash-reporting or error-monitoring service, so no crash reports or diagnostic dumps are sent from your device to a third party by the app.
8. Analytics
We keep a small amount of first-party product analytics, on our own servers, to understand which parts of the app people actually use. There is no third-party analytics service — no Google Analytics, no Firebase Analytics, no advertising or attribution SDK, and no session recording.
An analytics record consists of an event name (for example “a search completed”), which plan was in force, a small number of bucketed values such as a rounded search radius, and the date. The system that writes these records strips out identifying fields before anything is stored, and the analytics table has no column for an account identifier at all.
As a result, analytics records cannot be traced back to you, and we cannot use them to build a profile of an individual. Analytics records are deleted after 400 days.
This website sets no cookies and runs no analytics or tracking scripts. The app stores your preferences and session in your device's own local storage, not in cookies.
9. What we do not collect
- No advertising identifier and no device identifiers such as IMEI, MAC address or Android ID.
- No name, postal address or phone number. There is nowhere in the app to enter them and nowhere in our database to keep them.
- No contacts, photos, files, microphone or camera access. The app does not request these permissions.
- No precise location. The permission is not requested and the value is not stored.
- No payment card or bank details.
- No browsing history from outside Transit Hunter, and no cross-app or cross-site tracking.
- No sale of personal information to anyone, ever, and no sharing for advertising purposes.
10. How we use information
- To provide the service — finding transits near your saved places, ranking them, and telling you whether they are worth the trip.
- To send the alerts you asked for, at the lead time and outside the quiet hours you chose.
- To keep you signed in across sessions and devices.
- To apply your plan — the free plan's daily search allowance and the features included with Plus.
- To process and verify subscriptions bought through Google Play, and to handle billing problems.
- To keep the service secure and available, including rate limiting and fault diagnosis.
- To understand product usage in aggregate, through the identifier-free analytics described above.
We do not use your information for advertising, for profiling, or for automated decisions that have legal or similarly significant effects on you.
12. How long we keep information
| Information | Kept for |
|---|---|
| Your account, saved places, watches and equipment | Until you delete them, or delete your account |
| Sign-in codes | 15 minutes, single use, then deleted |
| Sign-in sessions | 30 days, or until you sign out |
| Alerts sent to you | 180 days |
| Transit events found for you | 90 days, or longer while an alert still refers to one |
| Daily search counts | 30 days |
| Weather forecast cache | 7 days. It is keyed by coarse area and shared between users, not attributed to anyone |
| Analytics records | 400 days. They contain no identifiers |
| Subscription and billing records | While your subscription exists, and afterwards for reconciliation, until you delete your account |
| Server logs | Retained by our hosting provider for a limited period for operational and security purposes |
13. Deleting your account and data
From inside the app
Open Settings and choose Delete my account. This removes your account and, in the same operation, everything attached to it: your saved places, your watches, your alerts and their history, your equipment profiles, your push registrations, your sign-in sessions and your subscription record. It happens immediately and cannot be undone.
You can also delete an individual saved place on its own, without deleting your account.
See it before you delete it
Settings also offers Export my data, which downloads everything we hold about you as a file, so you can see exactly what deletion will remove before you remove it.
By email
If you can no longer open the app, email transithunter@embarc.co.in from the address associated with your account and ask us to delete it. We will verify the request and act on it, normally within 30 days.
14. Your choices
- Use the app without an account — no email address required.
- Refuse the location permission and type place names instead. Everything still works.
- Turn off notifications in your device settings, or delete your watches.
- Export everything we hold, from Settings.
- Correct your saved places, labels and settings by editing them in the app.
- Delete individual places, or your entire account, at any time.
- Ask us a question about any of the above at transithunter@embarc.co.in.
Depending on where you live, local law may give you further rights over your personal information. Write to us at the address in section 20 and we will respond to any request we are required to honour.
15. Security
- Everything is encrypted in transit. The app and the website communicate with our servers over HTTPS only. The released Android app is built against a fixed HTTPS address and cannot be pointed elsewhere, and plain HTTP is not permitted in a release build.
- Session tokens are stored only as one-way hashes, so a copy of our database could not be replayed as a login. Sign-in codes are stored the same way.
- The data is coarse by construction. We store approximate locations rather than precise ones, so even a worst-case disclosure does not reveal a doorstep.
- The Android app disables Android's automatic backup, so its local data is not copied off your device to cloud backup by default.
- Access to production systems is limited to those who need it to operate the service.
No service can promise perfect security, and we do not. What we can say is that the amount and precision of what we hold has been kept deliberately small.
16. Where information is stored
Transit Hunter's servers and database are hosted on Fly.io, and the production machine and its storage are currently located in Singapore.
The third-party services listed in section 11 — Google, Resend, Open-Meteo, OpenStreetMap and OpenFreeMap — operate their own international infrastructure, so information sent to them may be processed in other countries.
If you use Transit Hunter from outside Singapore, your information will therefore be transferred to and processed outside your own country.
17. Children's privacy
Transit Hunter is a tool for astrophotography planning. It is not directed to children under 13, and we do not knowingly collect personal information from children under 13.
If you believe a child under 13 has provided us with personal information, contact us at transithunter@embarc.co.in and we will delete it.
18. Changes to this policy
We may update this policy as the product changes. When we do, we will revise the effective date at the top of this page and publish the new version here.
If a change materially affects what we collect or how we use it, we will give notice in the app before the change takes effect. Continuing to use Transit Hunter after a change means you accept the updated policy.
19. Governing law
This Privacy Policy and any dispute arising out of it are governed by the laws of India, and are subject to the jurisdiction of the courts at Agra, Uttar Pradesh, India.
20. Contact us
For any question, request or complaint about privacy, write to us:
39, Old Vijay Nagar Colony,
Agra – 282 004, India
Email: transithunter@embarc.co.in
We aim to answer within 30 days.