How Viewpoint works offline

Viewpoint is built to work in the field — on a clifftop, in a forest, anywhere a signal drops. Your device holds the real copy of your data, capture and the on-device tools run without a connection, and a network call is never the only way to see what you’ve already captured. Maps are the exception: the map imagery for an area you haven’t viewed needs a connection, and there are no offline maps yet. A handful of extras — the AR Scout’s terrain silhouette, a Location’s time zone, sky events, and satellite transits — do use the internet, in the ways set out below; none of them need an account, and syncing and live weather stay part of Max.

Works without a connection

• Capturing a Location — location, the auto-stamped sun position, and your notes are saved on the device immediately.
• Browsing your library — every Location, photo, note, and saved map you’ve captured is available with no connection.
• Editing — renaming Locations, editing notes, organising lists.
• The field calculators and the sun, moon, and Milky Way almanac — every calculation runs entirely on your device, for any date and place.
• AR Scout — the live sky overlay, the arc, time-scrubbing, and planning all run on-device. One part of it doesn’t: see Needs a connection below for the terrain silhouette.
• The light meter and Studio’s publishing tools — on-device.
• The sky parts of Conditions — darkness, the sun, the moon, and the Sky events tile (meteor showers and the Milky Way core window) are worked out on your device for any place and date, so they stay current with no signal. The rest of the Conditions page is live data; see Needs a connection.

Works offline once you’ve opened it with a connection

A few tools reach our server the first time, then keep working from what your device already has:

• Sky events (meteor showers, eclipses, and the rest of the almanac’s event calendar) — the app reads them from an on-device cache that’s kept current whenever you’re online, so once you’ve opened the list at least once, it stays usable with no connection.
• Satellite transits — the orbital data behind ISS, Tiangong, and Hubble predictions is cached on your device too. It’s refreshed every so often when you’re online; if you’re offline for a while, predictions still work from what’s cached, and the app tells you how fresh that data is (stale orbital data makes a prediction less precise — see Satellite transits).
• A Location’s time zone — resolved once (needs a connection) and then remembered on your device for that Location from then on. A Location you open for the very first time with no connection falls back to your phone’s own time zone instead, and says so on screen — right if you’re shooting near home, potentially wrong if you’re not.

Your Locations and their pins always show on the map, online or not — they live on your device. The map imagery underneath them is a separate thing; see The map itself below.

Capture and the library need Pro (a one-time purchase) or Max (a subscription). Everything else that runs on your device is Free. Locations already on your phone stay readable on Free; adding or editing them needs Pro. Once you’re on Pro or Max, a capture made offline is not lost — it is saved locally immediately. With Max it’s also queued and syncs to our servers the next time you have a connection. On Free and Pro there is no Viewpoint account and nothing goes to our servers: on iPhone and iPad your captures sync across your devices through your own iCloud instead. On Android, Free and Pro are single-device — if you want your library kept in step across more than one Android device, that’s Max. (Android’s own Auto Backup may still copy your library to your Google Drive unless you turn it off in Android Settings → Google → Backup — that’s a device-replacement safety net, not sync; see the privacy policy for the full picture.)

Needs a connection

• AR Scout’s terrain silhouette — the ridgeline that hides the sun or moon behind real terrain is computed on our server for where you’re standing. There’s no offline fallback for it yet: the scout tells you plainly when it isn’t available rather than guessing at a horizon, and the rest of the scout keeps working (see AR Celestial Scout).
• Find Your Viewpoint’s place suggestions on iPhone — the step that names real places to stand asks a language model online; the timing and geometry behind every result are still computed and checked on your device. (Max only.)
• The Conditions tab — forecasts, the hourly card, the fog, golden light, clear night, snow, storm light and aurora tiles, light pollution and Your places’ alerts are live data and need Max. They refresh when you are online and show the last known values, with their age, otherwise. Pull down on a page to refresh it when you are back online.
• Light pollution — a place’s reading is loaded once, then kept on your device; offline you see the last saved reading and when it was loaded.
• Syncing between devices, including compressed photo copies (not a backup of your originals; see Photo storage). (Max, and Pro through your own iCloud on iPhone and iPad.)
• Photo upload — by default photos upload on Wi-Fi only, to spare your mobile data. This is configurable in Settings.
• The map imagery — see below.

The map itself

Viewpoint’s map streams its imagery from the map provider as you pan and zoom. Unlike your data, that imagery is not stored for offline use:

• Your Locations and pins always show — they live on your device, so they appear whether you’re online or not.
• The map underneath them needs a connection. If you arrive somewhere new with no signal, your pins can sit on a blank background until you’re online again.
• In Explore on your phone, the map is Google Maps while you’re online with the Max plan, and the OpenStreetMap map otherwise. Open Explore without a connection and it uses the OpenStreetMap map, with your pins and plan unchanged.
• A “download this area for offline use” option — the way Google Maps and similar apps work — isn’t available yet. It’s something we’re looking into; it has not shipped.

We’re spelling this out because your data is stored on your device first, and today that covers your data — your Locations, photos, notes, and plans — not the map imagery itself. If your trips take you beyond cellular coverage, plan around that for now.

Sync, briefly

Sync runs in the background when you come back online — you do not have to do anything. With Max it syncs through our servers; with Pro, through your own iCloud on iPhone and iPad (on Android, Pro stays on the one device). If two devices edited the same Location while offline, the most recent edit wins.

Note: You will never be signed out for being offline. A dropped connection or an expired token does not log you out or hide your data — your captures stay on the device and on screen.