SkySort User Guide
Take a photo of clouds and identify their type through advanced machine learning technology.
Table of Contents
Getting Started
How do I identify my first cloud?
On the Identify tab, tap "Take Photo" to capture a cloud with your camera, "Photos" to choose an image from your photo library, or "Files" to import an image from your device storage. SkySort identifies the cloud on your device and opens the Review screen, which shows the cloud type, the confidence score with a quality rating, and the other likely types under "Other Possibilities". If the result looks wrong, tap "Change" or tap one of the other possibilities. Tap "Save Observation" to add it to your history, or "Discard" to start again.
What is the sky picture at the top of the Identify tab?
It's the sky above you right now, drawn from Apple Weather's current conditions for your area: cloud at each height, the sun or moon in its real position, rain, snow, fog, and clouds drifting with the wind. A badge such as "Now · 51% · mostly low cloud" says how much of the sky is covered and by what. For an hour after you photograph the sky nearby, your photo takes its place, with how long ago you took it; tap the photo to open that observation.
What cloud types can the app identify?
SkySort can identify 12 different cloud types: Cumulus (fair weather clouds), Altocumulus (mid-level patches), Cirrus (high, wispy clouds), Stratocumulus (low, lumpy layers), Cirrocumulus (high, rippled clouds), Cumulonimbus (towering storm clouds), Contrail (aircraft trails), Stratus (low, uniform layers), Nimbostratus (dark, rain-producing), Altostratus (mid-level gray sheets), Cirrostratus (high, thin sheets), and Clear Sky.
What does the confidence score mean?
The confidence score (shown as a percentage) indicates how certain the machine learning model is about the classification. Higher percentages mean the model is more confident in its prediction. The app uses a default threshold of 60%. A result below the threshold can still be saved: as "Unknown", or as a type you choose yourself.
Capturing and Importing
Can I import photos I've already taken?
Yes. You can import cloud photos from Photos (SkySort reads the photo's own location and date from its EXIF metadata, if it has them) or Files (JPEG, HEIC, or PNG images from iCloud Drive or other storage locations). Large photos are scaled down automatically when you import them.
What image formats are supported?
SkySort supports JPEG (.jpg, .jpeg), HEIC (.heic, .heif), and PNG (.png) formats. Images can be up to 30 MB, at least 360 pixels on the shortest side, and at most 12,000 pixels on the longest side.
Does the app save location data with my observations?
Yes, if you allow location access and "Save Location" is on in Settings. Camera captures save your current location. Imported photos keep the location stored in the photo, if there is one. Turn on "Use Current Location When Importing" in Settings to use your current location for imported photos that have none. With Precise Location turned off for SkySort in iOS Settings, photos are saved without a location, since an approximate position isn't accurate enough to record where a photo was taken.
Understanding Classifications
What if the confidence is below the threshold?
If the top prediction is below your confidence threshold (default 60%), the Review screen says "Low confidence — may be saved as Unknown. Try a clearer photo of the sky." You can still save it as Unknown, or tap "Change" to choose the right type yourself. Unknown observations appear in your lists as "No confident match". You can adjust the confidence threshold in Settings > Classification (range: 50%–90%).
Can I see multiple predictions?
Yes. Every classification shows the top prediction and the next two under "Other Possibilities", each with its confidence score. Tap a possibility to save the observation as that type instead. This helps you understand what the model detected and learn about similar cloud types.
Can I correct a classification?
Yes. On the Review screen, tap "Change" to choose from every cloud type, or tap one of the other possibilities. After saving, open the observation and tap the edit (pencil) button to change its type at any time. A corrected observation shows "Changed by you", and the model's original answer is kept in its note. Tap "Learn about…" on the Review screen to read about the type before you save.
Weather Data
Does the app capture weather conditions?
Yes. When you save an observation that has a location and was taken within the last hour, SkySort fetches the weather conditions from Apple Weather, including temperature, atmospheric pressure, humidity, wind speed and direction, cloud cover percentage, visibility, UV index, and weather condition. This applies to camera captures and to recent photos you import. You can turn this off in Settings > Weather > Capture Weather Data.
Why doesn't my imported photo have weather data?
Weather is only added for photos taken within the last hour, because Apple Weather reports current conditions and can't say what the sky was doing when an older photo was taken. A photo also needs a location for weather to be fetched.
Can I choose between Celsius and Fahrenheit?
Yes. Go to Settings > Units and select either Metric (Celsius, meters, hPa) or Imperial (Fahrenheit, feet, inHg). All data is stored in metric units internally—the unit preference only affects how data is displayed. Your choice applies on all your devices signed in to the same Apple Account.
Sky Outlook
What is the Sky Outlook?
The Sky Outlook card on the Identify tab shows the cloudwatching prospects for the hours ahead. It sums them up in a sentence, names the layer doing most of the covering ("Mostly high cloud"), and charts high, mid-level, and low cloud hour by hour for the next 24 hours (or 12 on narrower screens and at larger text sizes). It also shows when the evening's golden hour starts and when the sun sets. Tap the card to open the full outlook.
How do I read the cloud layers chart?
The chart is stacked like the sky: high cloud on top, low cloud at the bottom. Blue is clear sky; the whiter a cell, the more of the sky that layer covers. The strip along the top marks daylight, golden hour, and night. Layers overlap, so they don't add up to the total cover, which the full outlook prints under each time mark.
What's in the full outlook?
The full outlook shows the next good window for cloudwatching. It also shows Sun & light, with today's daylight bar, sunrise, sunset, both golden hours, and where you are in the day now. Then come the cloud layers chart with total cover, and "What to look for": the cloud families each layer may bring, from cirrus up high to cumulus down low. Last is an hour-by-hour list. Pull down to refresh.
What are golden hour reminders?
Golden hour is the warm, low light before sunset—the best light for photographing clouds. Turn on Settings > Notifications > Golden Hour Reminders, and SkySort reminds you 15 minutes before it starts each evening. Times are calculated on your device from your location, and reminders are kept up to date whenever you open the app.
Managing Observations
How do I view my observation history?
Tap the History (clock) button at the top of the Identify tab, or tap "View All" under Recent Observations. Your observations are listed with thumbnails, cloud type, date, and confidence. Switch between the list and a map of where each observation was taken with the buttons at the top. Tap an observation to see its photo, details, location, weather, notes, and tags.
Can I add notes to my observations?
Yes. Open an observation and tap the edit (pencil) button. You can change its cloud type, write a note (up to 2,000 characters), add up to 20 tags for organization, and record notable features like mammatus formations, a halo, or unusual color.
Can I search my observations?
Yes. In History, use the search field to find observations by cloud type, notes, or tags. Tap the More (•••) button to sort by date, confidence, or cloud type, or to filter by cloud type, date range, or minimum confidence.
How do I delete an observation?
Swipe left on an observation in History and tap Delete, or open the observation and tap the delete (trash) button. Deleting removes the photo and the observation on all your synced devices, and can't be undone.
iCloud Sync
How does iCloud sync work?
When enabled, SkySort automatically syncs your observations across all your devices signed in with the same Apple Account. Observations sync via iCloud, photos are stored in your private iCloud storage, changes made on one device appear on all devices, and deletions are propagated across devices. After turning iCloud Sync on or off, quit and reopen SkySort for the change to take effect. The iCloud Status row in Settings shows how syncing is going.
Which settings sync between my devices?
Your units, confidence threshold, haptic feedback, and golden hour reminder settings follow you across devices signed in to the same Apple Account. Location and weather settings, and iCloud Sync itself, stay set separately on each device.
What happens if I'm offline?
SkySort works offline. You can capture and classify clouds (ML runs on-device), save observations locally, and view your existing observations. An "Offline" banner appears while you're disconnected. When you reconnect, observations automatically sync to iCloud, and the Sky Outlook and weather data update.
Data Export
Can I export my observation data?
Yes. SkySort offers two export formats: CSV (spreadsheet format with all observation data) and PDF (formatted report with images and details). To export, open History, tap the More (•••) button, select "Export CSV" or "Export PDF", choose your export options, tap "Export", and share via the system share sheet. The export includes the observations currently shown, so search or filter first to export just some of them.
What export options are available?
When exporting, you can choose to include or exclude Location Data (leave it out to keep GPS coordinates private), Weather Data, Notes and Tags, and Technical Details like model version and device info.
Learning About Clouds
What is the Learn tab?
The Learn tab contains a Cloud Encyclopedia with detailed profiles of all 12 cloud types: about, altitude range, appearance, how they form, what weather they indicate, fun facts, similar clouds, and related types. It also contains glossary entries for meteorological terms, special sky phenomena (halos, sun dogs, iridescence, virga, crepuscular rays, and lenticular clouds), and the ID Helper, which asks a few questions about what you see to help you identify a cloud. Use the search field at the top to find a cloud type, term, or phenomenon quickly.
What do the altitude categories mean?
Clouds are grouped by altitude: High Clouds (above 20,000 ft) include Cirrus, Cirrocumulus, and Cirrostratus. Middle Clouds (6,500-20,000 ft) include Altocumulus and Altostratus. Low Clouds (below 6,500 ft) include Cumulus, Stratocumulus, Stratus, and Nimbostratus. Cumulonimbus has Vertical Development and can span all altitudes. Special categories include Contrails and Clear Sky. Altitudes are shown in the units you choose in Settings.
Statistics
What statistics does the app track?
The Stats tab shows total observations, average confidence, and your most common cloud type. It also tracks your current and longest streaks of days with an observation. Your Sky Collection shows how many of the 12 sky types you've spotted, and achievements are earned for milestones like First Light, 10 Observations, and a 7-Day Streak. Charts show observations by cloud type, your activity over the last 30 days, and a map of where you've observed.
How is observation quality determined?
Each observation is assigned a quality indicator based on confidence: Excellent (90-100%), Good (70-89%), Fair (50-69%), or Uncertain (below 50%).
Troubleshooting
Why won't the camera work?
Ensure you've granted Camera permission in iOS Settings > SkySort > Camera. Restart the app. Check that your device's camera is functioning properly. Try importing a photo from your library instead.
Why is location data missing?
Location may be missing if Location Services are disabled for SkySort or you denied location permission, Precise Location is turned off for SkySort, a GPS signal was unavailable at capture time, an imported photo has no location of its own and "Use Current Location When Importing" is off, or "Save Location" is disabled in Settings. To turn location on, go to iOS Settings > SkySort > Location > While Using the App, with Precise Location on.
Why isn't the Sky Outlook or live sky showing?
Both need your location and an internet connection to fetch the forecast from Apple Weather. Allow location access for SkySort and check your connection; until a forecast arrives, the Identify tab shows a simple illustration instead of the live sky. Per-layer cloud cover (high, mid-level, and low) requires iOS 18 or later; on iOS 17 the outlook shows total cloud cover only.
Why does the top of the Identify tab show the drawn sky instead of my photo?
Your photo is shown there only for an hour after you take it, and only if it was taken within about 25 km of where you are now. A photo synced from another device appears there as soon as it has finished downloading.
Observations aren't syncing across devices.
Check that iCloud Sync is enabled in Settings on all devices and that you quit and reopened SkySort after turning it on, that you're signed in to the same Apple Account on all devices, that you have an active internet connection and available iCloud storage space, and that iCloud Drive is enabled in iOS Settings > [Your Name] > iCloud. The iCloud Status row in Settings shows any sync problem.
How do I send diagnostic information to support?
In Settings > Support, turn on "Allow Diagnostics Export", then tap "Export Diagnostics". This creates a file with your device and app settings, recent errors, and SkySort's log entries from the last hour. Nothing leaves your device until you choose where to send it.
Privacy and Security
What data does the app collect?
SkySort is privacy-first. The app only collects photos you explicitly capture or import. Location data is collected only if you grant permission and enable it, and weather data only for observations that have a location. There are no analytics or usage tracking, and no data is shared with third parties. To fetch the Sky Outlook and live sky, an approximate location (rounded to about a kilometer) is sent to Apple Weather.
Is my data private?
Yes. All data is processed on-device (ML classification runs entirely on your iPhone or iPad), stored locally in your device's secure storage, synced privately using your private iCloud storage, not uploaded to external servers, and controlled by you: you choose what to save, export, and share. You can delete everything at any time in Settings > Data Management > Delete All Data.
Can I use the app without iCloud?
Yes. iCloud sync is completely optional. Turn off "iCloud Sync" in Settings, then quit and reopen SkySort, and all observations remain local to your device. You can still export data manually and no Apple Account is required for core functionality.
Technical Information
What iOS version is required?
iOS 17.6 or later. Compatible with iPhone and iPad. Per-layer cloud forecasts in the Sky Outlook require iOS 18 or later, and SkySort uses the Liquid Glass design on iOS 26 and later.
Does the app work offline?
Yes. Core features work offline, including capturing photos, classifying clouds (ML runs on-device), saving observations locally, viewing existing observations, and browsing the Learn tab. Fetching weather data, the Sky Outlook, and the live sky, and syncing to iCloud, require an internet connection.