How PolyDrive compares

Last verified 3 September 2026, against the version each product ships today. Every claim below links to the source it came from, so you can check it yourself — and so you can tell when this page has gone stale. A comparison table with no date on it is one you have no way to audit. If you are new to mounting altogether, or unsure how it differs from sync, start with the reasoning and come back to the rows.

PolyDrive is not the only way to open remote storage in Finder, and the honest starting point is what these tools have in common. Mountain Duck, ExpanDrive, CloudMounter and PolyDrive all mount storage into Finder, stream file contents on demand instead of syncing everything to disk, and connect straight to your provider without routing files through a server of their own. All four are good at that. This page is only about the places where they actually differ — and the shortest version is this: they all open clouds, and only PolyDrive also puts the things on your own desk in the same Finder window, an Android phone on a cable and a Linux disk in the card reader.

How that first row is counted, since a number invites suspicion. Each figure comes from that product's own list of what it connects to — published on the site for three of them, and in the source tree for rclone — and those lists are not built the same way. Ours is the longest partly because it is the most granular: 19 of PolyDrive's 47 entries are ready-made presets for S3-compatible providers — Cloudflare R2, Backblaze B2, Wasabi, Storj, Hetzner and the rest — which share a single backend between them, so the number of genuinely distinct backends behind the 47 is 26. CloudMounter counts “Amazon S3” once and reaches those same endpoints through a Server endpoint field on its S3 connection.16 The rclone figure is its own backend list with the machine's local disk taken out, along with the ten backends that wrap another remote rather than reaching storage of their own — the same exclusion we apply to ourselves, and its home page's “over 70” counts products the way our 47 does.14 Read the row as what it is: how much you are handed already configured, not how many pieces of code each app contains.

One caveat on the two guided-setup rows, because you would find it anyway. Several of those providers publish an S3- or WebDAV-compatible endpoint — Alibaba OSS, Tencent COS and Huawei OBS all speak S3; OpenList, Koofr and a Seafile server with its SeafDAV extension enabled all speak WebDAV. So an experienced user can reach some of them by hand through a generic S3 or WebDAV connector in any of these apps. What PolyDrive gives you is the provider itself in the list, with its own endpoint format, its own required fields and its own quirks already handled — one Seafile drive is one library, an OpenList mount needs the right WebDAV path, OSS accepts only virtual-hosted-style addressing. That is the difference those rows are about: picked from a list versus configured from documentation.

Deliberately absent from this table: price. Every product here changes its pricing on its own schedule, and a table like this one goes stale quietly. For our part — PolyDrive is a one-time purchase with no subscription and no separate charge for future updates; the current price is whatever the Mac App Store shows you. Check each of the others on their own site.

What a seek costs

Every app on this page fetches file contents on demand, and Apple's File Provider API has a call for fetching a range of a file rather than all of it. Whether an app uses that call, and in what size pieces, is the difference between jumping around a 1.3 GB video and downloading it. Nobody in this category publishes a number for it. Here is ours, and CloudMounter's, measured the same way on the same afternoon.15

The test is one command against a part of a file that has never been downloaded: read 64 KB somewhere in the middle, then ask the disk how much actually arrived. On PolyDrive it looks like this.

$ du -k video.mp4                                         # 1.29 GB; this part untouched
232028

$ dd if=video.mp4 of=/dev/null bs=64k count=1 iseek=12800 # read 64 KB, 800 MB in
65536 bytes transferred in 0.76 secs

$ du -k video.mp4                                         # 4 MiB arrived, and no more
236124

A second read, at 1000 MB, cost another 4 MiB and nothing else. Run the identical test on a video in Dropbox through CloudMounter 4.18 and the first read lands 32 MiB; a seek to 150 MB lands another 32 MiB.

Eight times the data for the same seek — that is the whole finding, and it is worth saying carefully. CloudMounter is not downloading whole files: it implements ranged fetching properly, and a read outside a piece it already holds fetches only the next piece. Its piece is simply 32 MiB where ours is 4 MiB. On a video you scrub through, that is the number you feel. Two things this measurement is not: a speed comparison — the two files sit behind different providers, so compare the sizes and ignore the seconds — and a verdict on Mountain Duck or ExpanDrive, neither of which is installed here. We have not measured them, so this page does not say anything about them.

And the half of this that is not to our credit. Fetching ranges only helps when the program opens the file itself — VLC's or IINA's own File › Open, a script, the command line. Double-click a video in Finder, or use Open With, and macOS materialises the entire file before handing it to any application. That is how File Provider behaves for every app on this page and for iCloud Drive itself, and it is not something we can opt out of. A macFUSE mount has no such thing as a partly-downloaded file, so a double-click there starts playing immediately — one of the real reasons CloudMounter's direct-download build still offers that mode, and rclone only has it.

And if you already use iCloud, Dropbox, OneDrive or Google Drive

Those four are not really competitors — they are what you already have, and their own apps are free. If everything you work on lives inside one of them, you do not need PolyDrive. It is for the case where your files are scattered across several places instead, and only some of those places have an app of their own.

PolyDrive mounts Dropbox, OneDrive and Google Drive as well, and for those three on their own it is usually not the better choice — their own apps are free and know their own service best. It earns its place when they are two of the six places your files actually live, and you would rather have all six in one Finder sidebar than six menu-bar icons competing for your disk.

Using it from a script — or an AI agent

A mounted drive is an ordinary path on your Mac: ~/Library/CloudStorage/PolyDrive-<drive>/. Not an API and not a sync folder — a directory that ls, cat, rsync, Python's open() and any coding agent already know how to use. Nothing has to learn your provider's SDK, and no credentials go anywhere near the script: it sees files, PolyDrive keeps the keys in the Keychain.

In practice that means you can point a coding agent — Claude Code, Cursor, whatever you use — at a folder on your Seafile library or your OpenList instance and have it read, edit and write there, with no per-provider integration in between. The same goes for backup scripts, batch image processing, or a Makefile that happens to read from a bucket. Here is that working, measured on a Cloudflare R2 drive: 8

$ ls ~/Library/CloudStorage/PolyDrive-CloudflareR2/
blob-8M.bin   readme.txt   icon-512.png   privacy.html   ...

$ cat readme.txt                     # fetched on demand
PolyDrive ext4 test card

$ echo "hello" > notes.txt           # uploaded to the bucket

$ du -k blob-8M.bin                  # nothing on disk yet
0

$ dd if=blob-8M.bin bs=64k count=1   # read just the start
65536 bytes transferred in 0.55 secs

$ du -k blob-8M.bin                  # one 4 MB chunk, not all 8 MB
4096

$ dd if=blob-8M.bin bs=64k count=1   # the same read, now local
65536 bytes transferred in 0.00016 secs

To be clear about what is and isn't unique here. Any app that mounts through the File Provider API gives you a POSIX path — ExpanDrive does, Mountain Duck 5 in Integrated mode does, and an rclone mount does too. This section is not a claim that PolyDrive is the only way to let a script or an agent work on remote files. What differs is the same thing the table above is about: which storage is one click from being that path. If your files live on a Seafile server, an OpenList instance or a Huawei OBS bucket, PolyDrive is the shorter route to having them somewhere your tools can just open.

Three things worth knowing first

macOS guards that folder. ~/Library/CloudStorage is a protected location, so the program reading it — Terminal, iTerm, your editor, an agent's host process — needs Files and Folders or Full Disk Access permission in System Settings › Privacy & Security. An agent running inside its own sandbox may not be able to reach the mount at all, however you set that permission.

A recursive scan is a download. Files stay dataless until something reads them, so grep -r or find -exec across a whole mount will pull every file it touches — real bandwidth, and on a metered bucket a real bill. Reads are ranged, so targeted ones stay cheap: in the session above, reading 64 KB at the start of an 8 MB file pulled a single 4 MB chunk rather than the whole thing. A blind full-tree search gets no such discount. Scope the path you hand to a script, and tell an agent which subfolder to stay in. If a script or an agent is going to read the same folder repeatedly, right-click it in Finder and choose Keep Available Offline — the download happens once and stays, so the second and tenth run cost nothing.

Not every backend can rename. FTP and Seafile drives have no server-side rename, so the common write-to-a-temp-file-then-rename-into-place pattern fails there. Write in place on those, or stage the temp file on your local disk and copy the finished result across.

Where each one is the better answer

Choose rclone if you are comfortable in a terminal and want the broadest backend list in existence for free. PolyDrive covers fewer services; it just doesn't ask you to write a config file or install a FUSE layer to use them. The two are not exclusive, either: where rclone reaches something PolyDrive has no entry for, it can serve that remote on your own machine and PolyDrive can mount it — a path we test rather than assume, written up in the bridge guide.

Choose Mountain Duck if you need SharePoint, or if you already live in Cyberduck — it shares that codebase and that protocol breadth. SMB and OpenStack Swift are no longer reasons: PolyDrive mounts SMB shares through macOS's own SMB client and keeps them mounted, and Swift is in the picker.

Choose ExpanDrive if you want this for nothing, or if some of the machines are not Macs. It is free for personal use and for any organisation where fewer than ten people use it in a year, it runs on Windows and Linux as well as macOS,10 and on the Mac it mounts through File Provider exactly as PolyDrive does.6 If your team is on Files.com it is also the same vendor as your server side.2 PolyDrive has nothing to offer on any of those: it is a paid Mac-only app that talks to whatever you already have.

What you accept in exchange is a product that has stopped growing. The fifteen services ExpanDrive lists today are the same ones it listed in January 2023 — three and a half years without a net addition — and its own comparison page says it does “not currently ship dedicated MEGA or pCloud support”, with OpenStack Swift filed alongside them as a reason to buy someone else's product.11 You also cannot audit what an update changed: ExpanDrive publishes no release notes we can find anywhere, and the feed it used to publish them on now returns 404.12 And its own security page says your credentials are on their way off your machine — versions “2025 and earlier do not store your credentials … in the Cloud”, and when the web client it plans for 2026 ships, “we will begin to store your credentials in the Cloud”.13 PolyDrive keeps them in the macOS Keychain, and has no server to put them on.

Choose CloudMounter if you need a real volume rather than a folder. Besides rclone it is the only one here that still mounts through macFUSE, and a macFUSE mount is a volume in /Volumes — which is what a tool that will not look inside ~/Library/CloudStorage, or one that wants a path outside a protected location, is actually asking for. Everything else on this page, PolyDrive included, gives you a folder there and cannot give you anything else. The costs are the kernel extension itself, and that the App Store build does not offer that mode at all.9

Choose PolyDrive if your storage is self-hosted or regional — a Seafile library, an OpenList instance, an Alibaba OSS or Tencent COS or Huawei OBS bucket — or if you want the things on your own desk in the same window: an SMB share on the LAN, an Android phone on a USB cable, an ext4 disk or a Raspberry Pi SD card, none of them needing a second app.

Switching from another mount app

30% off if you are coming from a paid competitor. If you have already paid for Mountain Duck, ExpanDrive, CloudMounter or another paid mounting app, email [email protected] with your receipt or a screenshot of the licensed product and we will send you a discount link. It applies to PolyDrive's one-time purchase, so there is no subscription to cancel afterwards and no separate charge for future updates. One per person.

Sources

1. Mountain Duck lists its supported protocols on its home page: FTP, SFTP, WebDAV, SMB, Amazon S3, Google Cloud Storage, OpenStack Swift, Microsoft Azure, Backblaze B2, Google Drive, Dropbox, OneDrive, SharePoint Online, Box, Nextcloud & ownCloud, and the local filesystem. mountainduck.io
2. ExpanDrive: “ExpanDrive mounts Amazon S3, Backblaze B2, Box, Dropbox, Google Drive, iDrive E2, Nextcloud, OneDrive, SharePoint, Wasabi, and any standard SFTP, FTP, or WebDAV server.” The same page describes it as “built by Files.com”, “a Files.com product”, and says “the cloud connectors mounting your drive on macOS, Windows, and Linux are the same ones that run on Files.com's high-performance cloud File Orchestration Platform”. expandrive.com
3. CloudMounter lists Dropbox, Google Drive, Microsoft OneDrive, Amazon S3, SFTP, FTP, WebDAV, Box, Backblaze B2, pCloud, MEGA and OpenStack Swift. cloudmounter.net
4. rclone documentation: “Mounting on macOS can be done either via built-in NFS server, macFUSE (also known as osxfuse) or FUSE-T.” rclone.org
5. Mountain Duck 5 press release, 19 August 2025: the new Integrated connect mode “leverages native APIs on Windows and macOS… This eliminates the need for device driver installation or network mount.” mountainduck.io/changelog
6. ExpanDrive: “ExpanDrive uses macOS's modern File Provider API — the same one Apple built for iCloud and Dropbox… No kernel extension, no reboot, no security prompts at every login.” expandrive.com/mac
7. Mac App Store listings, checked 15 August 2026: PolyDrive, Mountain Duck, CloudMounter. A search of the Mac App Store returns no ExpanDrive listing; ExpanDrive distributes from its own site.
8. Measured on macOS 26.5.2 with a Cloudflare R2 drive, 24 August 2026. Output trimmed for width; timings depend on your connection and on how far the bucket is from you.
9. CloudMounter documents three ways of mounting: a “macOS Native Drive” available “since macOS 11.3” with “support for working with files offline”; a “macFuse Drive”, which “is not available in the version of CloudMounter distributed through the App Store”; and a “Network Drive” needing no extra components, of which the vendor warns that “when using this type of drive mounting and performing a large number of simultaneous file operations, the list of files may take a long time to load or the disks may be disconnected”. So the answer for this row is whichever of the three is in use — and on the App Store build, never macFUSE. CloudMounter's pages never name File Provider, but the native mode is one: on 7 September 2026 we found its App Store build registering a File Provider extension (pluginkit -m -p com.apple.fileprovider-nonui lists com.eltima.cloudmounter.mas.mountprovider), and its mounted files are dataless in the way only a File Provider item is. cloudmounter.net
10. ExpanDrive's licensing page: the app “is free for personal use”, and also free “for enterprises where fewer than 10 people use ExpanDrive across the enterprise during a calendar year”; a paid licence “costs $29/month and covers use by up to 10 people”. Its system-requirements page lists Windows, macOS 11+ and 64-bit Linux builds. docs.expandrive.com
11. ExpanDrive's integrations page listed fifteen services on 3 September 2026: Amazon S3, Backblaze B2, Box, Dropbox, FTP, Google Cloud Storage, Google Drive, IDrive e2, Nextcloud, OneDrive, OneDrive for Business, SFTP, SharePoint, Wasabi, WebDAV. The Internet Archive's capture of the ExpanDrive home page on 1 January 2023 lists the same set. The MEGA, pCloud and OpenStack Swift wording is from their own CloudMounter comparison page, under the heading “Pick CloudMounter if…”. expandrive.com/integrations, expandrive.com/compare/cloudmounter
12. Checked 3 September 2026: there is no changelog or release-notes page in ExpanDrive's sitemap, in its documentation index (llms.txt), or on its download page, and the release-note feeds it published until at least January 2025 — updates.expandrive.com/release_notes/expandrive and …/expandrive7 — now return HTTP 404, with the whole host redirecting to the marketing site. Version numbers are dates, so you can see that a build shipped; the current one is 2026.08.25. You cannot see what is in it.
13. ExpanDrive's security page: “ExpanDrive versions 2025 and earlier do not store your credentials (passwords, keys, and authentication tokens) in the Cloud… We are working on a Web-based client for ExpanDrive that we intend to release in 2026. When we do, we will begin to store your credentials in the Cloud. We will provide clear notice when this transition occurs.” Read 3 September 2026; this is a stated intention, not something that has shipped. docs.expandrive.com/security
14. Each figure is from the product's own list of what it connects to. PolyDrive's was counted 17 September 2026; the other four were counted 7 September 2026 and are unchanged since. PolyDrive: 47 entries in the app's Add Drive picker. Two groups of those share one backend between them — 19 are presets for S3-compatible providers, and 4 more (WebDAV itself, Nextcloud / ownCloud, Nutstore and OpenList / Alist) are presets over WebDAV — which leaves 26 distinct backends. SMB shares and ext2/3/4 disks are separate features and are not in that picker. Mountain Duck: 16 named on its home page; it reaches further through connection profiles a user installs themselves, which are not part of the shipped list. ExpanDrive: 15 — its own integrations page is headed “All fifteen. One drive letter.” CloudMounter: 12 on macOS, and fewer on Windows. rclone: 57. Its source tree carries 70 backend directories; two of those are build machinery (all, overview), ten wrap another remote rather than reaching storage of their own (alias, archive, cache, chunker, combine, compress, crypt, hasher, memory, union), and one is the machine's own disk (local). The same exclusion is applied to PolyDrive's 47: local ext2/3/4 disks are left out of it, and so is SMB — which PolyDrive does mount, through macOS's own client rather than from the picker, so that omission costs us one rather than flattering us. rclone's home page separately says “Over 70 cloud storage products support rclone”; that counts products the way our 47 does, since its single S3 backend alone reaches dozens of named providers. On the stricter backend rule the two numbers are 57 for rclone and 26 for PolyDrive. Neither rule flatters everyone, so both are here. mountainduck.io, expandrive.com/integrations, cloudmounter.net, rclone.org, github.com/rclone/rclone
15. Measured 7 September 2026 on macOS 26.5.2, both apps in their Mac App Store builds (PolyDrive 2.0, CloudMounter 4.18), each file freshly undownloaded before the first read. PolyDrive: a 1 351 001 061-byte video in a Cloudflare R2 bucket, du -k rising by 4096 KB after a 64 KB read at 800 MB and by 4096 KB again after one at 1000 MB. CloudMounter: a 234 959 992-byte video in Dropbox, du -k rising to 32 768 KB after a 64 KB read at the start and to 65 536 KB after one at 150 MB. The same 32 MiB step appeared on two other CloudMounter drives, and a read inside a piece already held costs nothing further. Do not read the timings as a speed comparison: the two files sit behind different providers.
16. CloudMounter's own support article for an Amazon S3 connection lists a Server endpoint field that “allows getting access to S3 compatible cloud storages like Wasabi, S3For. Me, Hyperstore, Minio, etc.”, plus a path-style/virtual-hosted addressing switch offered for non-Amazon servers. Its FAQ keeps a table of services it does not list but can reach this way, naming Wasabi, DigitalOcean Spaces, Minio, Ceph, DreamObjects and Open Telekom Cloud. So this is configuration from documentation rather than an entry in the picker — the same distinction the guided-setup rows are about. Read 7 September 2026. help.electronic.us, cloudmounter.net/faq

Mountain Duck, ExpanDrive and CloudMounter are trademarks of their respective owners; rclone is an independent open-source project. PolyDrive is not affiliated with, endorsed by, or sponsored by any of them. The statements above reflect each vendor's own published information on the date at the top of this page and may have changed since. Found something out of date or wrong? Email [email protected] and we will correct it.

A one-time purchase, no subscription. macOS 15.4 or later.