You have a NAS in the basement or a Nextcloud at a hosting provider, and you want new iPhone photos to land there – automatically, without an iCloud subscription and without Apple seeing the pictures. The apps for that have existed for years. What no guide tells you: almost all of them only back up while you open the app regularly. “You need to keep the app opened and active to upload new photos”, a user writes in the Nextcloud forum in summer 2026; “It only works when I open the app and manually click the button”, another in the Synology community. That’s not the developers’ fault, it’s iOS. This article explains what the system allows in the background, compares seven ways and tells you which one is right for your NAS.
The short version
- iOS decides when apps run in the background. “Background App Refresh” is a request to the system, not a guarantee – and with a locked iPhone it’s often nothing at all.
- What runs reliably: uploads an app has handed to the system (background URLSession), and since iOS 27 the system uploading new photos by itself – WebDAV Browser uses both since version 1.4.
- Vendor apps: Synology Photos and Qfile Pro are free, but one declares identifiers in its privacy label and the other needs location services for the background. Synology Photos sits at 3 stars in the US store.
- PhotoSync backs up via geofence or while charging, but may only work in the background for three minutes. Free only in reduced quality.
- Immich is the best self-hosted photo library, but needs a Docker server and depends on Background App Refresh.
- Prices and store data as of November 7, 2026.
At a glance: which way for whom
Any NAS, Nextcloud or Storage Box over WebDAV, and it should run without your help
Hands uploads to iOS; since iOS 27 the system uploads new photos by itself. Originals, up to ten backups, every file verified on the server. Camera backup is part of Premium.
A Synology NAS, and you want to browse the photos on the NAS too
Synology Photos
Free, with face and place recognition on the NAS. Background backup unreliable per the community, privacy label with identifiers.
Your own photo library with AI search, running your own server
Immich
Open source, originals, duplicate detection, maps. Needs Docker and depends on iOS Background App Refresh.
Transfer everything in one go now and then, also to a PC
PhotoSync
Transfer via geofence, while charging or by hand. Originals only with Pro ($5.99 once), background run limited to three minutes.
Nextcloud with shares and Talk
Nextcloud app
Free and open. Photo upload is the app’s sorest spot – with a WebDAV client as a backup you’re safe.
What iOS allows in the background, and what it doesn’t
On Android a backup service simply keeps running. On the iPhone, iOS freezes an app the moment you leave it and wakes it again in only four cases:
| Mechanism | When iOS wakes the app | What happens with a locked iPhone | Who uses it |
|---|---|---|---|
| Background App Refresh | When the system has time; learns from your usage pattern, doesn’t fire at all in Low Power Mode | Rarely to never | Nextcloud, Synology Photos, Immich, most apps |
| Location services / geofence | When entering or leaving a place; needs “Always” location permission | Works, costs battery | PhotoSync (Premium), Qfile Pro |
| Background URLSession | Never – but uploads the app handed to the system beforehand are finished by iOS itself | Handed-over files get uploaded | WebDAV Browser, Nextcloud (chunked uploads only with the app active) |
| New photos uploaded by iOS 27 | Automatically when new photos are in the library; the app doesn’t have to run | Works | WebDAV Browser since version 1.4 |
The decisive difference is in rows three and four. Background App Refresh is a request: iOS wakes the app for a few seconds when convenient – and cuts it off as soon as the upload takes too long. That’s why photos pile up with almost all apps until you open them again; that’s why the Nextcloud client notes in its own bug tracker that large chunked uploads only run with the app active. A background URLSession, on the other hand, hands the file completely to the system; iOS uploads it even when the app has long been frozen. And since iOS 27 the system can upload new photos on its own, without the app running first. What remains is the one rule that applies to everyone: force-quit an app in the app switcher and iOS cancels running transfers.
Seven ways compared
iCloud Photos sits in the first column as a reference – not because we recommend it, but because it’s the yardstick for “runs without your help”.
| Criterion | Our appWebDAV BrowserViovenia | iCloud PhotosApple, reference | Synology PhotosSynology | Qfile ProQNAP | NextcloudNextcloud GmbH | PhotoSynctouchbyte | Immichopen source |
|---|---|---|---|---|---|---|---|
| Destination | any WebDAV server: NAS, Nextcloud, Storage Box | Apple cloud | Synology NAS with the “Synology Photos” package | QNAP NAS | Nextcloud server | WebDAV, SMB, SFTP, FTP, PC, cloud services | your own Immich server (Docker) |
| Runs without opening the app | yesuploads handed to the system; iOS 27 uploads new photos itself | yes | partlyBackground App Refresh; only with the app open per the community | partlyonly with location set to “Always” | partlyBackground App Refresh; forum: app must be open | partlygeofence or while charging, 3-minute window | partlyBackground App Refresh |
| Originals in full quality | yesoriginal file, HEIC stays HEIC | yes | yes | partlyHEIC conversion optional | yes | partlyPro only; free version reduced and as JPEG | yes |
| Several destinations or albums separately | yesup to 10 backups, by kind or album | no | not verified | partlytime range selectable | not verified | yesseveral destinations | partlyalbums selectable |
| Every file verified on the server | yesconfirmed via PROPFIND | not verified | not verified | not verified | not verified | not verified | not verified |
| Wi-Fi only | yesper backup | partlycellular can be disabled | yes | yes | yes | yes | yes |
| Price | Premium; 7-day free trial | iCloud+ from $0.99/month for 50 GB | free | free | free | free in reduced quality; Pro $5.99 once, Premium $6.49/year | free, own server required |
| Privacy label | Data Not Collected | – | Linked to you: identifiers | Not linked: location, diagnostics | Data Not Collected | Not linked: purchases, identifiers, diagnostics | not verified |
| Minimum iOS | 26 | – | 17 | 16 | 17 | 15 | not verified |
Legend:yespartlynonot verified
As of November 7, 2026, US App Store, vendor documentation and community forums. “Background App Refresh” = Apple’s mechanism that grants apps background time based on your usage pattern.
The ways one by one
Synology Photos is the obvious route for Synology owners: the app backs up the library into the “Synology Photos” package on the NAS, which knows faces, places and albums. Two things you should know. First, the app sits at 3.0 stars in the US store and declares identifiers linked to you – unusual for a backup app. Second, background upload is the perennial topic of the Synology community: users report in 2026 that the backup only runs once they open the app and trigger it manually. According to a community member, Synology doesn’t use Apple’s mechanism for background uploads. The older DS file does the same with less comfort, was last updated in September 2025 and sits at 2.8 stars in the US store.
Qfile Pro by QNAP backs up automatically, but requires location permission – the app uses location services to get woken up in the background. That works, costs battery and is a privacy compromise. Optionally the app only uploads while the device is charging, and converts HEIC photos if you want.
Nextcloud ships a photo upload that has frustrated forum users for years: “as soon as the device is locked … the upload stops”, one thread says; in another the upload stalls after 200 photos because the server limit kicks in. The “delete after upload” option exists; an October 2026 review complains it doesn’t take effect. The client is free, open source and collects no data – but if the backup matters to you, don’t rely on it alone.
PhotoSync is the transfer specialist: to NAS, PC, WebDAV, SMB, SFTP and cloud services, with geofencing (“when arriving home”), while charging or via Shortcuts. The catch is in its own help pages: iOS gives the app three minutes in the background, then it’s over until the next trigger. And the free version transfers in reduced quality and converts HEIC and RAW to JPEG – “I didn’t know the free version transferred low quality versions”, a user writes in October 2026. Pro for $5.99 once lifts that, Premium ($6.49 a year) adds automatic transfer.
Immich is the project that rebuilds Google Photos on your own server: originals, duplicate detection, faces, map, AI search, all open source. You need a server with Docker and some maintenance. The iOS app backs up in the background via Background App Refresh – that is, whenever iOS allows it, as XDA users sum it up. As a photo library Immich is the best choice on this list; as a silent backup it has the same limit as all the others.
FileBrowser Professional ($14.99 once, no data collected) backs up the library to up to two destinations – NAS over SMB, Nextcloud over WebDAV, Google Drive. How reliably that runs in the background isn’t documented by the vendor; reviews report syncs restarting every ten minutes. As an all-round file manager it’s still recommendable, as our comparison of WebDAV apps shows.
WebDAV Browser: a backup that iOS finishes by itself
When we built camera backup for WebDAV Browser, the requirement was: it has to run without you thinking about it. So we decided against Background App Refresh and for the mechanisms iOS guarantees:
- Uploads belong to the system. Every file goes to iOS as a background task. Leave the app and the system keeps uploading; failed uploads retry automatically, large videos get more time.
- Since iOS 27 without opening. With version 1.4, iOS uploads new photos and videos on its own, even when the app is closed. On iOS 26 the backup runs as soon as you open the app and is finished in the background.
- Verified, not assumed. Some routers and NAS boxes confirm an upload without creating the file. So after every upload the app checks via PROPFIND whether the file sits on the server with the right size. Only then does it count as backed up; “Check backed-up files” reconciles the ledger with the server on request.
- Up to ten backups. Photos and videos separately, single albums into their own folders, a second copy on another server. Each backup with its own Wi-Fi rule and time range; “Test Backup” creates a test file beforehand and deletes it again.
- Originals. The app uploads the original file from the library, HEIC stays HEIC. Nothing is deleted on the iPhone – the backup is a copy, not a move.
- Visible. Live progress on the lock screen as a Live Activity, a notification when everything is done, a status card on the home screen.
What’s missing: the app only speaks WebDAV, no SMB. And camera backup belongs to Premium – seven days free on your first subscription, one purchase covers iPhone, iPad and Mac.
Set up in five steps
Enable WebDAV on the NAS
Synology: install the “WebDAV Server” package and enable HTTPS on port 5006. QNAP: enable WebDAV in Control Panel under “File Services”. Nextcloud and the Hetzner Storage Box speak WebDAV out of the box; at Hetzner you have to enable it in the Console.
Create a dedicated user and folder
Create an account for the backup that may only write to one folder such as “Photos/iPhone”. If the phone gets lost, you revoke this account without changing your main password. With Nextcloud and two-factor authentication you need an app password.
Set up and test the server in the app
Enter the full address – for Nextcloud with the path /remote.php/dav/files/USERNAME/ – and run the connection test. A self-signed NAS certificate should be remembered deliberately by the app, not waved through wholesale.
Create the backup and do a trial run
Choose the destination folder, set the time range (only new photos or the whole library), set the Wi-Fi rule. Then start a test run and check on the NAS whether the first file arrived at full size.
Check after a week
Compare the number of photos from the last week in the library with the folder on the NAS. If files are missing, it’s almost always an app that iOS doesn’t wake in the background – then only an app that hands its uploads to the system helps.
Top tip
A NAS backup replaces iCloud Photos only for backing up, not for syncing. What you delete or rename on the NAS doesn’t change on the iPhone, and vice versa. If you want both, use Immich or Synology Photos as your library – and in addition a silent backup to a second place that touches nothing. A backup that can also delete isn’t a backup.
Frequently asked questions
Does the photo backup run when the iPhone is locked?
Only with apps that hand their uploads to the system: iOS finishes background URLSession transfers even on a locked device, and since iOS 27 it can upload new photos by itself. Apps that rely on Background App Refresh – Nextcloud, Synology Photos, Immich – run only when iOS gives them time, and mostly not at all on a locked device.
Why does Synology Photos only back up when I open the app?
Because the app depends on Apple’s Background App Refresh, which the system grants at its own discretion and only briefly. Users in the Synology community report in 2026 that the backup only runs after opening the app and triggering it manually. Remedies: allow Background App Refresh for the app, turn off Low Power Mode – or use an app that hands uploads to the system.
Are HEIC photos backed up as originals or as JPEG?
Depends on the app. WebDAV Browser, Synology Photos, Nextcloud and Immich upload the original file. PhotoSync converts HEIC and RAW to JPEG in the free version and reduces quality; only Pro transfers originals. Qfile Pro offers conversion as an option.
Can I have photos deleted from the iPhone after the backup?
Nextcloud offers the option, PhotoSync too; reviews report that it doesn’t take effect reliably with Nextcloud. WebDAV Browser deliberately deletes nothing on the iPhone: a backup that touches the source can destroy data if the upload was incomplete without anyone noticing. Delete by hand after you’ve seen the files on the NAS.
Do I still need iCloud Photos?
Not for the backup. iCloud Photos also keeps all devices in sync and saves space on the iPhone (“Optimize iPhone Storage”). A NAS backup offers neither. If you turn iCloud off, all originals live on the device – plan for the storage space.
What happens with Live Photos and videos?
All the apps mentioned back up videos, PhotoSync in reduced quality in the free version. With Live Photos – a photo plus three seconds of video – not every app backs up both parts. Check with a test run: if only the HEIC file sits on the NAS, the video is missing.