Can photos be used to analyze your health?
Only as context, not as a medical test: if you allow it, Daylumen reads recent photos on your iPhone to notice things like time outdoors, other people, late nights and days away from home, and sets them beside your Apple Health data. All of this happens on the device, photos, faces and location are never copied or uploaded, and nothing in the app is a diagnosis.
Photos can say things about a day that Apple Health cannot, such as whether you spent it outside. Here is exactly what Daylumen does with them.
Source: Daylumen's privacy policy (last updated October 11, 2026) and how the app behaves in version 1.11.1, checked 2026-10-14.
What the photo reading is for
Photos are an extra signal in the background. The daily reading is still about your sleep, activity and heart data from Apple Health. A photo can add something those numbers cannot tell, such as that last Saturday was spent outdoors, so that Daylumen can say whether days like that tend to go with better sleep for you.
What Daylumen takes from a photo
| Signal | How it is worked out | Where |
|---|---|---|
| Outdoor and nature days | Apple's Vision framework classifies the scene of the photo | On your iPhone |
| Days with other people | On-device face detection counts faces and smiles. It does not recognise who anyone is | On your iPhone |
| Late nights | The time the photo was taken, between 22:00 and 05:59 | On your iPhone |
| Days away from home | The photo's coarse location compared with where most of your photos are taken | On your iPhone |
What is kept is a short summary for each day, such as counts and labels. The privacy policy says your original photos, faces and location data are never copied, uploaded or transmitted. The app looks at recent photos, roughly the last six months, sampled evenly so that no single month dominates.
What it does not do
- It does not look at your body, face or skin to judge your health.
- It does not upload photos, or anything derived from them, to a server.
- It does not change or delete your photos. Daylumen only reads.
- It does not turn a pattern into a diagnosis. A line like days in nature go with longer sleep is a pattern in your own records, not proof of cause.
Permission and control
- Photo access is optional and asked for separately inside the app, not at first launch.
- You can allow all photos or only a selection in the iOS permission sheet, and revoke it at any time in iOS Settings.
- Deleting the app removes the results it cached on your device.
iOS has no read-only Photos permission, so the system prompt uses the same access level as apps that edit photos. Daylumen's behaviour is read-only, as above.
Is it worth turning on?
Daylumen works without photos. Turn them on if you want patterns about outdoor days, company and late nights alongside your health data, and leave them off if you would rather not grant the permission at all.
Frequently asked questions
Does Daylumen upload my photos?
No. According to its privacy policy, photos are read and analysed on your iPhone, and your original photos, faces and location data are never copied, uploaded or transmitted.
Does Daylumen look at my face or body to assess my health?
No. It counts faces to notice days with other people, and does not identify anyone or judge your body. It is a wellness read, not a medical device.
Do I have to allow photo access?
No. It is optional and can be revoked at any time in iOS Settings. The rest of Daylumen works without it.
Can I share only some of my photos?
iOS lets you allow a selection instead of the whole library. Daylumen reads the photos you allow.
Daylumen reads the health data already on your iPhone and tells you what it means for today.
Get Daylumen on the App StoreFree to download · iPhone · iOS 17 or later · a one-time in-app purchase unlocks the deeper tools