For the curious

Under the hood

You do not need any of this to use DRL-FileSync. It is here for people who like to know how things work, and for anyone comparing us with other services.

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Face recognition, on your own PC

Open “Mom” and see every photo of her. DRL-FileSync can group your photos by who is in them, and it does all of it on the PC you already own. No cloud, no upload, and it is off until you say yes.

Only on your PC

Your PC finds the faces and keeps the results in a small database next to your photos. Nothing is sent to our website, to the internet or to anyone else, so there is nothing for us to see.

Off until you turn it on

The app asks once when you set it up, and the answer is no unless you say yes. You can switch it on or off later in Settings, under People.

Groups only when it is sure

Blurry, tiny or turned-away faces are left alone. A face joins a person only when it is a very close match to faces already in that group.

Asks you when it is not

If a face looks a lot like someone but not enough to be sure, the app asks “Is this Mom?” with a quick Yes or No. It learns from every answer, and a No is never asked again.

Private by design

Photos in your Locked folder are never scanned. With encryption on, the face database is encrypted like your photo index and chat. Each person’s people stay in their own account.

Delete it any time

One button in the app, “Delete all face data”, makes your PC forget every face, person and name it found. Your photos are never touched.

How it works, for the technically curious
  • Finding faces: YuNet, a small open face detector (MIT licence).
  • Recognising them: SFace, an open model (Apache 2.0 licence) that turns each face into 128 numbers. Faces whose numbers are close belong together. Both models run on your PC, with no internet connection.
  • What it looks at: the PC’s own preview pictures of your photos, not the full files, one photo at a time with small pauses, so your PC stays usable.
  • What it keeps: the position of each face, its 128 numbers, and the names you give. Not a copy of the face picture. The small face pictures you see in the app are cut from your photo on demand.

Good to know: grouping is never perfect, which is why it asks. The first scan of a large library can take hours, and it runs while DRL-FileSync is open on your PC. Face data can count as sensitive biometric data in some places, so use it for photos you are comfortable grouping, and let people in your household know. It works on the photos of your own account.

How your data moves

DRL-FileSync websiteaccounts, pairing, plans
Your phone
Your PC

The website only introduces your devices to each other. It never receives your photos, videos, files or messages.

The technology, in plain words

DRL-FileSync is built so that your files move between two devices you own, and so that you do not have to trust us, or a hard drive thief, with them.

Direct, never relayed

Away from home your phone and PC open a direct, encrypted connection (WebRTC, the technology behind video calls). Our website only helps them find each other, then steps aside. There is no relay server in the middle, so your files cannot pass through one.

Paired by keys, not passwords

Scanning the QR code gives your phone and your PC each other's public key. Every request the phone makes is signed with its private key and checked by the PC, and the phone only talks to the PC whose key it was given. No password is ever sent to your PC.

Fast and pinned on your Wi-Fi

At home the phone finds the PC on your network and talks to it over HTTPS, pinned to that PC's own certificate. A look-alike device on your network cannot pose as your PC.

Transfers that cannot silently go wrong

Every file gets a SHA-256 fingerprint. The PC says which ones it is missing, uploads resume where they stopped, duplicates are skipped, and each file is checked against its fingerprint when it arrives.

Encryption you control

Optional AES-256-GCM, with a fresh key for every file and 1 MiB authenticated chunks: tampering is detected and videos still jump to any point instantly. With encryption on, your photo index, previews and chat history are encrypted too.

A key that is not left on the disk

Your PC holds your encryption key in memory only, never on its disk, and forgets it when DRL-FileSync closes. After you sign in, the PC fetches the key from your account. The website stores that key locked with a secret kept on our server, so a forgotten password does not mean lost files. This means DRL-FileSync is not end-to-end encrypted: we never receive your photos or files, but the locked key does sit on our server. With Offline mode on, the PC also saves the key on its own disk, sealed by its security chip and your Windows account.

Your library, recognised anywhere

Each photo folder carries a small hidden description, readable only with your key when encryption is on. Plug that drive into a new PC and DRL-FileSync recognises your library and takes it in, with no re-upload.

Starts when your phone needs it

Quit DRL-FileSync on your PC and a tiny helper keeps listening. When your phone looks for the PC, it starts DRL-FileSync again, hidden in the tray. You can switch this off on the PC, or on each phone.

Sign a PC in with your phone

A new PC shows a QR code. Scan it with a phone that is already signed in, tap to confirm, and the PC signs in and pairs with that phone in one step. No password typed on a shared or new computer. Prefer typing? Email and password still work, side by side.

A guided first set-up

A full-screen guide asks for one thing: a working folder, where everything from your phone lands. Backup folders on another drive are optional and can wait. It warns you about nearly full, network or removable drives, and recognises a DRL-FileSync library that is already there.

Nothing runs when you are signed out

If nobody is signed in on a PC, DRL-FileSync does not sit in the background and its wake-up helper does not run. Sign out and the helper is removed from Windows start-up too. It comes back when you sign in.

Ordinary files, no lock-in

Unless you turn encryption on, your photos and files are plain files in plain folders. Open them in Windows Explorer, copy them, move them. There is nothing to export and nothing that stops working if you leave.

For the technically curious
  • Remote link: a WebRTC data channel (DTLS) set up through our signalling service, using public STUN servers to find a route. Requests are carried over the channel exactly as they are on the Wi-Fi, with the same signatures.
  • Request signing: ECDSA P-256 over the method, path, a timestamp and the body hash. The PC rejects bad signatures and requests outside a short clock window.
  • On the Wi-Fi: HTTPS with a self-signed certificate made from the PC's own key; the phone accepts only a certificate holding the key it was paired with.
  • File encryption: AES-256-GCM, per-file keys derived with HKDF-SHA256 from your account key and a random salt, authenticated 1 MiB chunks, header and "last chunk" flag included in the authentication.
  • Data at rest on the PC: with encryption on, the photo index and chat database are stored with SQLCipher, and previews are encrypted files. Keys live in memory only.
  • Pairing and accounts: the website stores your account, your devices' public keys and your plan. It never receives photos, files, chats or private keys.

At home, your files never touch the internet

When your phone and your PC are on the same Wi-Fi, DRL-FileSync finds the PC on your network and sends everything straight to it. No upload to a server, no trip across the internet and back. This is Wi-Fi mode, and it switches on by itself whenever you are home.

Much faster

Files travel at the speed of your router, not your internet plan. Home internet uploads are often slow; your own network is usually many times faster, so a big backup finishes in minutes instead of hours.

No mobile data, no limits

Nothing is counted against your mobile data or your internet provider's monthly allowance, however many videos you back up.

Works without internet

If your internet is down but your Wi-Fi is up, backing up, browsing the gallery and opening files still work. If your files are encrypted, your PC also needs its key after a restart: turn on Offline mode and it keeps the key safely on its own disk, so it can start with no internet at all.

More private

Your photos and files never leave your network, so there is no outside connection for anyone to watch, and nothing is stored anywhere but your own PC.

Easier on your battery

A short, fast transfer over Wi-Fi keeps the phone's radio busy for much less time than a long upload over mobile data.

Nothing to set up

There is no switch to flip. DRL-FileSync uses Wi-Fi mode whenever your PC is on the same network, and moves to a direct, encrypted internet connection when you are away, on plans that include access from anywhere.

Offline mode: a switch in the phone's Settings (and in the Windows program) that makes DRL-FileSync stop using the internet altogether, on the phone and on the PC. They talk only over your Wi-Fi. Signing in, new phones, share links and plan changes wait until you turn it off. Once a day the PC asks the website only what your plan includes and when it ends, and sends nothing else. With encryption on, your PC then saves your key on its own disk, sealed by its security chip and your Windows account, so anyone who can sign in to that Windows account could open your files.

Good to know: in Wi-Fi mode the phone and the PC must be on the same network, and the PC must be on. Away from home, or if the PC is off, DRL-FileSync waits and carries on as soon as the PC can be reached.

How DRL-FileSync compares

With the big cloud services, and with the do-it-yourself options. We say where each one is better, too.

Against cloud storage services

 DRL-FileSyncGoogle Photos & DriveApple iCloudMicrosoft OneDriveDropbox
Free storage As much as your drives hold15 GB, shared with Gmail5 GB5 GB2 GB (Basic)
Where your files live On your own PCGoogle's serversApple's serversMicrosoft's serversDropbox's servers
Cost as your library grows Add a drive; the price does not changePaid storage tiersPaid storage tiersPaid storage tiersPaid storage tiers
Photo quality Always the originalOriginal, or the smaller "Storage saver" qualityOriginalOriginalOriginal
Encryption Optional; the key is kept in the PC's memory, never on its disk (unless you turn on Offline mode)Encrypted on their serversEnd-to-end if you switch on Advanced Data ProtectionEncrypted on their serversEncrypted on their servers
Backing up at home Direct over your Wi-Fi, no internet neededUploaded over the internetUploaded over the internetUploaded over the internetUploaded over the internet
Signing in a new computer Scan a QR code with your phone, or use email and passwordPassword, usually with a second checkApple ID, with a code on a trusted devicePassword, usually with a second checkPassword, with optional two-step
First set-up on a new computer A guide: one working folder, backup folders optionalInstall, sign in, choose foldersInstall, sign in, choose what to keepInstall, sign in, choose foldersInstall, sign in, choose folders
Reachable while your own PC is off No. Away from home the PC must be on Yes Yes Yes Yes
iPhone, web access, public share links Not yet (Android and Windows) Yes Yes Yes Yes

Against running it yourself

 DRL-FileSyncImmichNextcloudSynology Photos
What you need The Windows PC you already haveA server running Docker, with several containers including a databaseA web server and database stack (or Docker)A Synology NAS
Setting it up Install a program, scan a QR code, pick a folderCompose files, updates and backups are yours to manageInstall, configure and keep the server updatedSet up the NAS and its Photos app
Reaching it away from home Built in: a direct connection, no router changesYou arrange it (reverse proxy, VPN or port forwarding)You arrange it (domain and certificate, VPN or port forwarding)Synology's own service, or your own set-up
CostFree plan; paid plans add extrasFree and open source; you run the hardwareFree and open source; you run the hardwareThe NAS itself; the app is included
Face and smart search Faces: yes, optional and on your PC. Object search: not yet YesThrough apps Yes, on supported models
Phones and webAndroid and WindowsAndroid, iPhone and webAndroid, iPhone, web and desktopAndroid, iPhone and web
Always-on machine needed No. Your PC, when you want accessYes, a serverYes, a serverYes, the NAS

Free allowances and features were checked in October 2026. Providers change them, so see their own sites for today's details. Product names belong to their owners; DRL-FileSync is not affiliated with them.

DRL-FileSync is a good fit if

  • You already own a Windows PC that is on most of the day
  • You want to stop paying for storage that grows with your library
  • You want your photos at original quality on a drive you control
  • You want something that works after a QR code, not a weekend of setup

Look elsewhere if

  • You use an iPhone, or need to open files from any browser
  • You want public share links, or search by what is in a photo (objects, places) today
  • You need access while your PC is switched off
  • You do not want to look after a computer and its backups

The honest trade-off: a PC is yours to look after. If it is off, away from home you cannot reach your files, and if its only drive fails and you kept no second copy, your files are gone. DRL-FileSync can mirror everything to extra drives automatically, and it warns you when your backup shares a drive with the originals.

More questions

Is my data encrypted?

Encryption is optional. When you turn it on, your PC encrypts the photos, videos, drive files and chat attachments it stores, using AES-256-GCM, and decrypts them for you when you open them. A recovery key is kept on your account so a forgotten password does not mean lost files. Traffic between your devices is encrypted in transit either way.

How is DRL-FileSync different from Nextcloud, Immich or a Synology NAS?

Those are excellent, and some do more today (an iPhone app, a web gallery, search by objects). They also need a server or NAS that you set up, update and open to the internet yourself. DRL-FileSync is a normal Windows program: install it, scan a QR code, and your phone connects directly, at home or away, with no router changes and no always-on server.

What if my PC is stolen?

With encryption on, your files, the photo index, previews and chats on the PC are encrypted, and the key is kept in the PC's memory only, never written to its disk. Without encryption your files are ordinary files, so anyone with the PC could open them. Encrypting, and using a Windows password, matter.

How do I sign in on my PC?

Two ways, side by side on the sign-in page. Scan the QR code with a phone that is already signed in (in the app: Windows clients, then Add Windows client) and tap Sign it in, or type your email and password. Scanning also pairs that phone with the PC. The code works once and expires after ten minutes, and nothing is signed in until a phone you control says yes.

What do I have to set up on the PC?

One folder. A short guide asks for a working folder where everything from your phone is saved. Backup folders on a different drive are optional and can be added any time. You can change both later in Settings.

What happens if I quit DRL-FileSync on my PC?

A tiny helper with no window keeps running while you are signed in to DRL-FileSync. If your phone then looks for your PC, the helper starts DRL-FileSync again in the background. You can switch this off in the Windows program, and each phone can opt out in its own settings. If nobody is signed in, neither DRL-FileSync nor the helper stays running.

Do you scan my photos or use them for ads or AI?

No. Your photos live on your PC and our website never receives them, so there is nothing for us to scan, and DRL-FileSync has no ads. There is one optional feature that looks at your photos, and it runs only on your own PC: finding people. It is off unless you turn it on (see the next question). There is no cloud face or object search.

How does finding people work, and is it safe?

If you turn it on, your PC looks through your photos one by one, finds the faces and groups the ones that match, using two small open models that run on the PC itself. Nothing is sent to us or anywhere else. It groups a face only when it is very sure, and asks you “Is this the same person?” when it is not. Photos in your Locked folder are never scanned, and one button deletes everything it found. It is off until you say yes.

Which devices are supported?

Android phones and Windows PCs today.

Something not working? See Help and support for fixes to common problems, and how to reach us.