Privacy Policy

Last updated: 4 October 2026

Caelo is made by Paul Smith, an independent developer in Australia. You can reach me at hello@caelo.today about anything on this page.

I’ll keep this short and specific, because a privacy policy that hides behind lawyer-speak isn’t telling you anything.

The short version

Caelo has no accounts, no login, and no server of mine. Everything you create in the app — your sky profile, your horizon, your favourites, your session plan — is stored on your iPhone and nowhere else. I can’t see it. It never reaches me unless you send me a diagnostics file yourself, to get help with a problem.

Three things can leave your device, and only these three:

1. Your observing coordinates go to a weather service, so Caelo can tell you whether tonight is worth going outside for.
2. Apple handles your payment if you buy the Pro unlock.
3. A diagnostics file, only if you send it yourself. If something isn’t working and you’d like my help, Settings → Send Diagnostics lets you send me one. Caelo never sends it on its own.

That’s the whole story. The rest of this page is the detail behind it.

What Caelo stores on your device

All of this lives in Caelo’s own storage on your iPhone. None of it is uploaded to me unless you send it to me yourself with Send Diagnostics.

• Your sky profile — the coordinates of your observing site, the horizon outline you captured, and the name you gave the profile.
• Your saved locations — coordinates and the names you typed for them.
• Your favourites and your session plan — which objects from the catalogue you’ve starred or planned to observe.
• Your telescope selection — which of the built-in telescope presets you chose.
• A cached weather forecast for your site, so the app works when you’re out of signal.
• Calculated results — precomputed visibility data, derived from the above.
• App settings — whether you’ve finished onboarding, and your light/dark appearance choice.

Two of these are free-text fields you fill in yourself: your profile name and your location name. Whatever you type there is stored as you typed it, next to that site’s coordinates. If you’d rather not have your home address sitting in a field called “Location name”, call it something else — “Home” or “Back garden” works just as well, and the app never needs the real thing.

Caelo also writes short technical notes into iOS’s own system log, such as a file that failed to load. They contain no locations, names or ids, and iOS clears them on its own. Caelo itself passes them on only inside a diagnostics file you choose to send.

What leaves your device

Weather

To tell you tonight’s cloud cover, Caelo asks Apple’s WeatherKit service for a forecast. Before that request leaves your phone, Caelo rounds your coordinates to about a kilometre (two decimal places). The forecast is identical at that precision, so your exact spot — your backyard, your driveway — is never transmitted; only the neighbourhood-level pair is. The request contains those rounded coordinates, and it is authenticated as coming from the Caelo app the way any WeatherKit request is — but nothing in it identifies you: no name, no account, no advertising ID.

Caelo asks your phone for an approximate location, and rounds it itself to about a kilometre (a 0.01 degree grid) before it is used or saved. It does not rely on iOS to do that. Profiles you captured before version 1.0.1 may hold the exact coordinates your phone reported at the time. Those stay on your device, and they are never what is sent to Apple.

As with any network request, Apple will also see your device’s IP address, which is a rough indicator of where you are. That’s how the internet works rather than a choice Caelo makes, but you deserve to know it happens.

Weather data is governed by Apple’s own privacy policies. Caelo credits Apple Weather beside the forecast it shows you, and the terms and the exact credit Apple requires are on the WeatherKit legal attribution page.

The forecast that comes back is cached on your device so the app still works when you have no signal.

Payment

If you buy the Caelo Pro unlock, Apple handles the entire transaction. Caelo tells Apple which product you’re buying and Apple tells Caelo whether you own it. Your payment details, your Apple ID, and your purchase history are Apple’s to handle under Apple’s privacy policy — they never pass through Caelo, and I never see them.

Send Diagnostics (optional)

If something in Caelo isn’t working and you’d like my help, Settings → Send Diagnostics puts together a file that shows me what Caelo sees on your phone. Caelo never sends it. Nothing is sent in the background, and Caelo never asks you to send one. It’s there for when you want it.

Before anything leaves your device, Caelo shows you the whole file, exactly as it will be sent, and asks you to read it first. If you’re happy with it, tap Email Caelo and a new email opens with the file attached. The email is addressed to me at hello@caelo.today; you can change the recipient before you send. Nothing goes until you tap Send. If Mail isn’t set up on your iPhone, or you’d rather send it another way, you can share the file instead and choose where it goes, the same way you’d share a photo or a note. If you’d rather not, tap Cancel and nothing leaves your device.

The file contains:

• Message text — a short summary of the rest, which goes in your message: the version, your iPhone model, Pro, how many Sky Profiles and Locations you have, whether they loaded, and how many log lines follow.
• Build and device — Caelo’s version, build and build date, your iPhone model, iOS version, and your language and region setting.
• Caelo Pro — whether you’ve unlocked Pro, and whether the purchase check has run since launch.
• Location permission — whether you allowed Caelo to use your location, and whether iOS gives it approximate or precise location. Never where you are.
• Your Sky Profiles and Locations — exactly as Caelo stores them: the names you gave them, your horizon outlines, and when you captured them, with every position rounded first, plus the files’ sizes and any note on why one failed to load.
• Caelo’s log since you opened the app — the app’s own notes on what it did, such as a file that failed to load. These lines never contain coordinates, names or ids.

At the top of that screen, Caelo says, in these words: “Here is everything that will be shared. Please read it first. It includes the names of your Sky Profiles and Locations, with positions rounded to about a kilometre. No photos or camera images are included.” It also never includes exact coordinates (not even from profiles saved before 1.0.1), your Apple ID or payment details, any account, advertising or device identifier, or the logs or data of iOS itself or of other apps (from iOS it takes only your iOS version, iPhone model, and language and region setting).

If you send it to me, I use it only to work out what went wrong and fix it, and I keep it only as long as I need it for that. Ask, and I’ll delete it sooner. If you send it by email, I’ll also see your email address and the name on your email account, and I’ll use them only to reply to you. If you send it to someone else, it’s theirs to handle. The copy Caelo makes for sharing is deleted as soon as you close the screen.

Nothing else

To be explicit about the things Caelo does not do:

• No analytics. No usage tracking, no usage events recorded or sent, no session recording.
• No automatic crash or diagnostic reporting. Nothing leaves your device unless you expressly and explicitly choose to send it. Nothing is ever sent in the background, and nothing is sent without you knowing. A diagnostics file leaves your device only when you send it yourself, to get help with a problem (see Send Diagnostics, above).
• No advertising, no ad identifier, no third-party advertising SDKs.
• No tracking, as Apple defines it — Caelo never links your data to anything from other companies’ apps or websites, and never shares it with data brokers.
• No account, no sign-in, no cloud sync of your data by me. There is no Caelo server holding your information, because there is no Caelo server.
• No selling of anything to anyone. There’s nothing to sell, and I wouldn’t.

Permissions Caelo asks for, and why

Caelo asks for three things, and only uses them for what it says.

Location — Caelo needs to know where you’re standing to work out what’s visible from there and to fetch your local weather. Caelo requests location only while you’re using the app, never in the background. Caelo asks for your approximate location and rounds it to about a kilometre before it is used or saved with your sky profile; after that, the app uses the saved coordinates rather than tracking you. (Profiles captured before version 1.0.1 may hold the exact coordinates your phone gave the app then.)

Camera — used only as a live viewfinder while you mark the trees and rooftops on your horizon, so you can see what you’re pointing at. Caelo takes no photographs and records no video. No image or camera frame is ever saved, exported, or read by the app — the only thing kept from a horizon capture is a list of angles: how high your obstructions are, and in which direction.

Motion sensors — used to know which way your phone is pointing while you’re marking those obstructions. Nothing more.

You can withdraw any of these at any time in iOS Settings. Caelo will lose the matching capability, but it won’t misbehave.

Backups

Because Caelo’s data lives in your app’s normal storage, it’s included in your iPhone’s own backups — encrypted iCloud or computer backups, run by Apple’s settings, not by Caelo. That backup belongs to you and Apple; I have no access to it and no way to reach it.

Deleting everything

Settings → Delete All Data erases every piece of it: your profiles and their coordinates, your locations, favourites, session plan, telescope choice, the cached weather, and every calculated result. The app returns to first-run state. It’s immediate, it’s permanent, and it doesn’t need my involvement, because I hold no copy of it. The one exception is a diagnostics file you’ve sent me, because that’s no longer on your phone. Ask, and I’ll delete it. The notes Caelo wrote to iOS’s system log are out of its reach too, but they hold nothing that identifies you.

Deleting the app from your iPhone removes it all too.

Two honest footnotes. Your Pro purchase isn’t erased, because it isn’t Caelo’s to erase — Apple holds that entitlement against your Apple ID, which is what lets you restore it on a new phone. And deleting your data doesn’t revoke the iOS permissions you granted; those live in iOS Settings, where you can turn them off yourself.

Children

Caelo isn’t directed at children, and doesn’t knowingly collect anything from them. It has no accounts and no way to identify who’s using it.

Your rights

If you’re in the European Economic Area or the UK, the GDPR gives you rights over your personal data: to access it, correct it, delete it, take it with you, and object to how it’s used.

Caelo’s design answers most of these without anyone’s involvement, because the data is on your device rather than mine: you can see it in the app, edit it, and delete all of it with one button. There’s nothing to export, because none of it came to me. The one exception is a diagnostics file you chose to send me. Ask, and I’ll send you a copy or delete it. Where I process anything, the legal basis is the legitimate interest of making the app do the one thing you opened it to do. For location, it’s the permission you granted in iOS, which you can withdraw at any time. For a diagnostics file, it’s your own request for help.

If you believe I’ve mishandled something, you’re entitled to complain to your local data protection authority. I’d appreciate the chance to fix it first — hello@caelo.today.

Australian users: the same protections apply under the Privacy Act 1988 and the Australian Privacy Principles.

Data outside your country

Only two kinds of data travel. The rounded coordinate pair goes to Apple’s WeatherKit service, and because that request carries nothing identifying you, the transfer is minimal by design. A diagnostics file travels only if you send it, through the app you choose, and if you send it to me it reaches me in Australia.

Changes to this policy

If Caelo ever starts doing something new with your data, this page changes first and the date at the top changes with it. If a change is significant, I’ll say so in the app’s release notes rather than quietly editing the page.

What changed

Newest first. The version is the first release of Caelo that the change applies to.

• 4 October 2026 · from version 1.0.2 — Send Diagnostics now opens an email addressed to me at hello@caelo.today, with the file attached. You still read all of it first, you can change the recipient, and nothing goes until you tap Send. The sentence on the screen that says what the file includes was reworded.
• 3 October 2026 · from version 1.0.2 — Caelo can now put together a diagnostics file for you to send me when something isn’t working. You read all of it first, you choose where it goes, and Caelo never sends it itself.
• 20 September 2026 · from version 1.0.1 — Caelo now rounds your location to about a kilometre before it saves it with your sky profile, instead of saving the exact spot your phone reported. Profiles captured before 1.0.1 may still hold exact coordinates on your device.
• 3 September 2026 · from version 0.98 — The weather service changed from a third-party forecast provider to Apple’s WeatherKit. Coordinates are still rounded first, and nothing in the request identifies you.
• 22 July 2026 · from version 0.95 — Coordinates are now rounded to about a kilometre (two decimal places) before they are sent for the forecast.
• 20 July 2026 · from version 0.9 — The first version of this policy.

Contact

Paul Smith — hello@caelo.today

Caelo is an independent app made in Australia.