What is Cloud Sync?
Cloud Sync keeps your photos, videos, and related files synchronized between your Android device and cloud storage. The app offers three different synchronization modes, each designed for specific use cases. You can also choose whether to synchronize at the folder level or select individual files, and control which file types are synced.
Sync Modes
Upload Only Device → Cloud
What it does: Automatically backs up your photos and videos to the cloud. Changes on your device are uploaded to the cloud, but cloud changes don't affect your device files.
Best for:
- Backing up photos and videos
- Creating cloud copies of important media files
- One-way backup scenarios
- Sharing your albums or media files with others
Example Scenario: You take photos with your camera. The app automatically uploads them to the cloud. If someone else modifies a photo in the cloud (e.g., applies a filter), your original photo on the device stays unchanged.
Download Only Cloud → Device
What it does: Automatically downloads photos and videos from the cloud to your device. Changes in the cloud are downloaded to your device, but device changes don't affect the cloud.
Best for:
- Accessing photos and videos shared by others
- Keeping a local copy of cloud media files without affecting the cloud
- Receiving media files from family and friends
Example Scenario: Your family shares a folder of vacation photos in the cloud. The app keeps them updated on your device. If you accidentally delete a photo on your device, it will be re-downloaded from the cloud (if configured).
Two-Way Sync Bidirectional
What it does: Keeps both sides in sync. Changes on either side are automatically synced to the other side.
Best for:
- Working on photos and videos from multiple devices
- Collaborating with others on media projects
- Keeping media files truly synchronized everywhere
Example Scenario: You take a photo on your phone, and it appears in the cloud. Later, you edit the same photo on your computer, and those changes sync back to your phone. It works in both directions!
Sync Level Modes
What it does: You manually select individual photos or videos to sync. When you review your media after a photo session, you can mark specific files to upload to a specific folder in the cloud. Only the files you mark will be synchronized.
Best for:
- Curating specific photos from your camera roll
- Selecting only the best shots to backup
- Selective sharing of media files
- Having full control over what gets synchronized
- Professional workflows requiring selective media sharing
Professional Use Cases:
Real Estate Agent: You're selling multiple properties and have thousands of photos in your camera. For each client, you create a separate cloud sync rule and mark only the relevant property photos. Client A sees only their property photos, Client B sees theirs, and so on.
Wedding Photographer: After a wedding shoot, you have 800 photos. You review them and mark only the 100 best shots to upload to the couple's cloud folder. The test shots, duplicates, and out-of-focus photos stay only on your device.
Key Benefits:
- ✅ Full Visibility: You always see which media files are shared with whom
- ✅ Privacy Control: Each client/project only sees their relevant photos
- ✅ Storage Efficiency: Don't waste cloud storage on test shots and rejects
- ✅ Professional Presentation: Clients receive curated, high-quality content only
- ✅ Organized Workflow: Despite mixed camera roll, cloud folders are perfectly organized
- ✅ Flexible Sharing: Different rules for different clients/projects from the same device
What it does: You select folders or albums on your device which will be automatically synchronized. All photos and videos in the selected location are synced automatically without manual marking.
Best for:
- Automatic backup of all camera photos
- Syncing entire photo albums
- Backing up multiple albums at once to a single cloud folder
- Set-it-and-forget-it scenarios
- Complete folder mirroring
Example Scenario: You select your "Camera" folder for synchronization. Every photo you take is automatically uploaded to the cloud without any manual action from you. New photos appear in the cloud within minutes.
Example with Albums: You select Camera, Screenshots, and WhatsApp Images albums. Each album is automatically stored in its own subfolder in the cloud. You can add or remove albums from sync at any time directly from the album view.
Note: Folder-level sync is automatic and convenient but syncs everything in the selected folder or album.
SyncGallery offers two approaches to selecting which photos and videos to sync. Both achieve the same result — your media gets synced to the cloud — but they reflect different ways of thinking about your photo collection.
Approach 1: Select a Folder
This is the traditional, file-system approach. You pick a specific folder on your device (such as /DCIM/Camera) and optionally include its subfolders. This gives you precise control over exactly which directory is synchronized.
Best for users who:
- Are comfortable navigating the device file system
- Want to sync a folder that contains subfolders with a specific structure
- Need to sync a custom folder that doesn't appear as a gallery album
- Want to use the "monitor sub-folders" option to capture nested content
Example: You select /DCIM with "monitor sub-folders" enabled. This syncs everything inside DCIM, including Camera, Screenshots, and any other subfolders — all with their folder structure preserved in the cloud.
Approach 2: Select Albums
This is the gallery-oriented approach. Instead of thinking about folders, you select one or more albums as they appear in the gallery. Each album is automatically stored in its own subfolder in the cloud. You don't need to know or care where the photos are physically stored on the device.
Best for users who:
- Prefer working with albums as they appear in the gallery
- Want to back up several albums with a single sync rule
- Don't want to deal with file paths and folder structures
- Want to easily add or remove albums from sync later
Example: You select the Camera and Screenshots albums. In the cloud, a "Camera" and a "Screenshots" subfolder are created automatically. Later, you open the Downloads album and add it to the same sync rule with one tap — no need to open the rule settings.
Key Differences
| Feature | Folder | Albums |
|---|---|---|
| Selection method | Browse device file system | Pick from gallery albums |
| Sub-folder support | Yes, via "monitor sub-folders" toggle | Each album is its own unit |
| Multiple locations | One folder per rule | Multiple albums per rule |
| Cloud structure | Mirrors device folder hierarchy | One subfolder per album |
| Add/remove later | Edit the rule settings | Directly from the album view |
Which should I choose? If you just want to back up your photos and don't want to think about file paths, use albums. If you need to sync a specific directory tree or use sub-folder monitoring, use the folder approach. You can always switch later by editing the rule.
Download Behavior
When files need to be downloaded from the cloud, you can control how the app handles new files. This setting is particularly important for Download Only and Two-Way Sync modes.
What it does: When a new file needs to be downloaded from the cloud, SyncGallery first searches your entire device for an identical file (matching size and content). If found, it creates a mapping to that existing file instead of downloading a duplicate.
How it works:
- App receives a new file from the cloud that needs to be synced
- Before downloading, app searches your device for a file with identical size and content
- If identical file found: Creates a mapping, no download needed
- If no match found: Downloads the file to the specified location
Best for:
- When you already have some photos on both your device and the cloud
- Avoiding duplicate files and saving storage space
- Saving bandwidth (no need to download files you already have)
- Initial sync when you're setting up synchronization for existing photo libraries
Example Scenario: You have 1000 vacation photos on your device. Your friend shared a cloud folder with 800 of those same photos. With "Search Device" enabled, the app finds the 800 matching photos on your device and creates mappings without downloading duplicates. Only the 200 new photos are actually downloaded.
Note: The search looks for exact matches based on file size and content. Files must be identical to be matched.
What it does: Downloads files strictly to the device folder you specified in settings, preserving the relative folder structure from the cloud. No search for existing files is performed.
How it works:
- All files are downloaded to your specified device folder
- Subfolder structure from the cloud is preserved
- Example: Cloud path
/Photos/2024/January/photo.jpg→ Device path/DCIM/Sync/2024/January/photo.jpg - No duplicate checking - files are always downloaded
Best for:
- When you need exact control over where files are stored
- Maintaining organized folder structure from the cloud
- Fresh downloads to a specific backup location
- When you want predictable file locations
Example Scenario: You have a cloud folder /Work/Projects/ClientA with subfolders for different photo shoots. With "Defined Folder" mode set to download to /DCIM/Work, the app creates /DCIM/Work/Projects/ClientA on your device with the same subfolder structure.
Note: This mode always downloads files even if identical files already exist elsewhere on your device. Make sure you have enough storage space.
Which Mode Should I Choose?
- Search Device: Choose this if you want to avoid duplicates and save space. Ideal when merging existing photo collections.
- Defined Folder: Choose this if you want organized, predictable file locations. Ideal for clean, structured downloads.
File Types & Filters
When you create or edit a sync rule, the File types to sync dropdown controls what the rule will handle. Choose from three options based on your needs.
Photos & videos only (default)
What syncs: Standard image and video formats — JPEG, PNG, HEIC, AVIF, MP4, 3GP, WebM, MOV, and similar.
Ignored: Documents, archives, sidecar files, and other non-media files.
When to use: Almost every user. Matches the classic gallery-app experience and works with limited storage permissions.
Photos, videos, and sidecar metadata (XMP)
What syncs: Everything from the default mode, plus common photo-editor sidecar files: .xmp, .aae, .thm.
When to use: Photographers using Lightroom, Adobe Camera Raw, Apple Photos, or similar tools that store edit instructions in sidecar files next to the original photo.
All files matching custom patterns
What syncs: Any file type you describe with the include/exclude patterns below the dropdown.
When to use: Power users who want to back up documents (PDFs, office files), archives, scripts, or specific non-media files alongside their photos.
Important: Non-media files sync but do not appear in the gallery view — access them through your cloud provider's app, web interface, or a file manager app. Custom patterns require All Files Access permission (see the Permissions section below). Smart duplicate detection is media-only: non-media files always download without duplicate checking.
Include and Exclude Filters
When you choose the custom-patterns option, add wildcard patterns to the include and exclude lists. Include patterns say "sync these"; exclude patterns say "skip these". Exclude filters take priority over include filters.
Examples:*.* — all files*.jpg — JPEG photos only*.pdf — PDF documents*_backup.* — files ending in "_backup"
Example combination: include *.*, exclude *.tmp — sync everything except temporary files.
Permissions & All Files Access
SyncGallery starts with limited permissions by design. At first launch you were asked to choose between Media Only (photos and videos) and All Files (broad access under Android's Special app access settings). You can change this later in Android Settings.
When All Files Access is required
All Files Access is needed for these advanced features:
- File-level sync across multiple folders — picking individual files from folders the app hasn't been explicitly granted
- Smart duplicate detection at setup — scanning the device to match existing files against a cloud folder (photos and videos only)
- Custom file patterns — syncing non-media files like PDFs, XMP sidecars, archives
- Full SD card access and app-specific media folders (WhatsApp, Telegram) without per-folder prompts
- Background sync across many folders without user interaction each time
If you pick Media Only at first launch and later try to create a sync rule, SyncGallery will show a dialog explaining why All Files Access is needed. Without this permission, sync features are unavailable; the gallery and editor continue to work for browsing and editing existing media.
What All Files Access does NOT do
- Does not upload anywhere without your configuration — sync targets only the cloud account and folder you set up
- Does not process your files — files travel directly from your device to your cloud; we don't use intermediate servers
- Does not share your files with third parties — see the privacy policy for details
Configuration Options
1. Monitor sub-folders
When enabled, all nested subfolders will also be synchronized. This setting is available for Download, Two-Way Sync, and Folder Level Upload modes.
2. Verify file content when matching
By default files are matched by name and size only. Enable this setting to also compare content hash for more accurate but slower matching.
1. Delete in cloud when unmark (File Level Sync only)
When enabled: If you unmark a photo or video on your device, it will automatically be deleted from the cloud.
2. Delete in cloud when device file deleted
When enabled: If you delete a photo or video from your device, it will also be deleted from the cloud.
Warning: Deletions are permanent! Use carefully.
3. Update cloud files when modified on device
When enabled: If you modify a photo or video on your device (edit, crop, apply filter), the updated version is automatically uploaded to the cloud.
4. Re-upload to cloud if file was deleted there
When enabled: If someone deletes a file from the cloud, it will be re-uploaded from your device.
5. Re-upload to cloud if file was modified there
When enabled: If someone modifies a photo or video in the cloud, your original device version will overwrite their changes.
Warning: Use carefully! This will discard cloud changes.
1. Update device files when modified on cloud
When enabled: If a photo or video is modified in the cloud, the updated version is downloaded to your device.
2. Re-download from cloud if file was deleted on device
When enabled: If you delete a photo or video from your device, it will be re-downloaded from the cloud.
3. Re-download from cloud if file was modified on device
When enabled: If you edit a photo or video on your device, your changes will be discarded and the file will be re-downloaded from the cloud.
Warning: This will discard your local changes!
4. Delete on device when cloud file deleted
When enabled: If a file is deleted from the cloud, it will also be deleted from your device.
1. Delete in cloud when unmark (File Level Sync only)
When enabled: If you unmark a photo or video on your device, it will automatically be deleted from the cloud.
2. Update cloud files when modified on device
When enabled: Changes you make on your device are uploaded to the cloud.
3. Update device files when modified on cloud
When enabled: Changes made in the cloud are downloaded to your device.
4. Delete in cloud when device file deleted
When enabled: Photos and videos deleted from your device are also deleted from the cloud.
5. Delete on device when cloud file deleted
When enabled: Photos and videos deleted from the cloud are also deleted from your device.
Understanding Conflicts (Two-Way Sync Only)
What is a Conflict?
A conflict occurs when both you AND someone else (or another device) modifies the same photo or video before they sync.
Example:
- You edit a photo on your phone (offline)
- Meanwhile, someone edits the same photo in the cloud
- When your phone comes online, both versions exist
How Conflicts Are Resolved
When the app detects a conflict, it does not silently overwrite either version. Instead, you receive a notification for each conflicting file and are asked to choose what to do.
Available Actions:
- Keep device version — Upload your local version to the cloud, replacing the cloud copy
- Keep cloud version — Download the cloud version to your device, replacing your local copy
- Keep both — Save the cloud version as a separate file alongside your local version
- Skip — Do nothing for now; the conflict will be raised again on the next sync
To minimize conflicts:
- Sync frequently (especially before editing)
- Communicate with team members about who's editing what
- Consider using your cloud provider's web interface for real-time collaboration
Common Scenarios & Recommended Settings
Goal: Automatically backup all my camera photos to the cloud
Recommended Mode: Upload Only + Folder Level Sync
Recommended Settings:
- Sync Level: Folder Level (select Camera folder or Camera album)
- ✅ Update cloud when device file changes: ON (backup edited photos)
- ✅ Re-upload if deleted from cloud: ON (protect against accidental cloud deletion)
- ❌ Re-upload if modified in cloud: OFF (unless you want to enforce device version)
- ⚠️ Delete from cloud when deleted from device: Use carefully! (ON = cloud photos deleted when you clean up device)
Tip: Want to back up more than just Camera? Select multiple albums (Camera, Screenshots, Downloads, etc.) in one rule. Each album will get its own subfolder in the cloud, and you can add or remove albums later directly from the album view.
Goal: Share only my best photos with family
Recommended Mode: Upload Only + File Level Sync
Recommended Settings:
- Sync Level: File Level (manually mark photos)
- ✅ Update cloud when device file changes: ON (share edited versions)
- ❌ Delete from cloud when deleted from device: OFF (keep shared photos even if you clean up device)
- Share with: Add family members' email addresses
Goal: Keep local copies of photos shared by my family
Recommended Mode: Download Only
Recommended Settings:
- ✅ Update device when cloud file changes: ON (get latest versions)
- ❌ Re-download if deleted from device: OFF (you can choose which to keep)
- ❌ Re-download if modified on device: OFF (keep your local edits)
- ❌ Delete from device when deleted from cloud: OFF (keep local copies even if removed from shared folder)
Goal: Edit photos on phone and computer, keep everything in sync
Recommended Mode: Two-Way Sync + File Level
Recommended Settings:
- Sync Level: File Level or Folder Level (your choice)
- ✅ Update cloud when device file changes: ON
- ✅ Update device when cloud file changes: ON
- ⚠️ Delete from cloud when deleted from device: Your choice (ON = deletions sync everywhere)
- ⚠️ Delete from device when deleted from cloud: Your choice (ON = deletions sync everywhere)
Important: Sync frequently to avoid conflicts!
Tips & Best Practices
DO:
- Start with simple settings and adjust as needed
- Test with a small folder first before syncing large photo libraries
- Check your available cloud storage before enabling large syncs
- Sync important photos frequently to avoid conflicts
- Keep backups of critical photos outside of sync
DON'T:
- Enable all flags without understanding what they do
- Use Two-Way Sync for collaborative projects without coordinating with your team
- Rely on sync as your ONLY backup method
- Enable delete flags without testing on non-critical photos first
- Edit photos while offline without syncing afterward
BE CAREFUL WITH:
- Delete flags (deletions can be permanent!)
- "Rewrite" flags (they discard changes made elsewhere)
- Large photo/video syncs over mobile data (watch your data plan!)
- Syncing private photos to shared folders
- Folder-level sync with many subfolders (can sync a lot of files!)
Remember: SyncGallery only works with photo and video files - other file types are automatically ignored.