Zynk vs Syncthing

Syncthing is open-source and private, but it's a folder-sync engine: deletions propagate, its own FAQ says it isn't backup, and there's no official iOS client. Zynk is end-to-end encrypted too, and built to send something on purpose to the device you choose, on every platform including iOS.

Download Zynk Visit Syncthing

On-demand sending with a tray, chat, and preview

You send on purpose, not as a side effect of sync where deletions propagate to every device.
You want a native app with a menu-bar tray, not a browser admin UI.
You need iOS. Syncthing's FAQ says no official iOS client is planned.
You want a conversation, in-app preview, voice notes, PDF signing, share links, drop links, and a CLI under one account.

Feature by feature

Feature by feature, what Zynk does and what Syncthing does.

Feature	Zynk	Syncthing
Model	Pick files, choose where they go, send.	Background sync of configured folders. Deletions propagate between devices.
PlatformsZynk wins	Native apps on macOS, Windows, Linux, iOS, Android, and Android TV. Linux builds include Raspberry Pi and Steam Deck. CLI anywhere you can open a terminal.	Linux, Windows, macOS, FreeBSD, OpenBSD, Android. No official iOS client planned.
EncryptionEven	End-to-end encrypted. Only the receiver devices you send to can unlock the file.	TLS between devices. Explicit approval by cryptographic device ID.
AdministrationZynk wins	Native app on every platform.	Browser UI. No native desktop or mobile app.
Menu bar and trayZynk wins	Lives in the macOS menu bar and the Windows and Linux system tray. Drop a file onto a contact, paste a message, or see who's online without opening the main window.	Tray shows sync state and a link to the browser admin UI.
Finder and share menuZynk wins	Right-click "Send with Zynk" in Finder and Windows Explorer. Send from the iOS, Android, and macOS share menus.	No per-file send. Drop files into a synced folder managed through the browser UI.
ConversationsZynk wins	Every device and every contact gets its own chat: text messages, emoji reactions, edits, replies, and full history.	No UI for conversation.
Voice notesZynk wins	Record a voice note with a waveform inside the app and send it like any other file.	No.
In-app previewZynk wins	Optional preview for PDFs, video, audio, images, markdown, and code with syntax highlighting.	No. Files just appear in a folder.
PDF signingZynk wins	Open a PDF, draw or type a signature, send the signed copy back. No third-party portal.	No.
Share linksZynk wins	Yes.	No. Not a link product.
Drop linksZynk wins	Yes.	No.
Recipient choiceZynk wins	Recipient accepts and picks the device.	Sync replicates to every configured device. Deletions propagate without per-file consent.
CLIZynk wins	Yes, anywhere you can open a terminal.	CLI available, but for managing sync folders, not sending files.

Model

Zynk: Pick files, choose where they go, send.
Syncthing: Background sync of configured folders. Deletions propagate between devices.

PlatformsZynk wins

Zynk: Native apps on macOS, Windows, Linux, iOS, Android, and Android TV. Linux builds include Raspberry Pi and Steam Deck. CLI anywhere you can open a terminal.
Syncthing: Linux, Windows, macOS, FreeBSD, OpenBSD, Android. No official iOS client planned.

EncryptionEven

Zynk: End-to-end encrypted. Only the receiver devices you send to can unlock the file.
Syncthing: TLS between devices. Explicit approval by cryptographic device ID.

AdministrationZynk wins

Zynk: Native app on every platform.
Syncthing: Browser UI. No native desktop or mobile app.

Menu bar and trayZynk wins

Zynk: Lives in the macOS menu bar and the Windows and Linux system tray. Drop a file onto a contact, paste a message, or see who's online without opening the main window.
Syncthing: Tray shows sync state and a link to the browser admin UI.

Finder and share menuZynk wins

Zynk: Right-click "Send with Zynk" in Finder and Windows Explorer. Send from the iOS, Android, and macOS share menus.
Syncthing: No per-file send. Drop files into a synced folder managed through the browser UI.

ConversationsZynk wins

Zynk: Every device and every contact gets its own chat: text messages, emoji reactions, edits, replies, and full history.
Syncthing: No UI for conversation.

Voice notesZynk wins

Zynk: Record a voice note with a waveform inside the app and send it like any other file.
Syncthing: No.

In-app previewZynk wins

Zynk: Optional preview for PDFs, video, audio, images, markdown, and code with syntax highlighting.
Syncthing: No. Files just appear in a folder.

PDF signingZynk wins

Zynk: Open a PDF, draw or type a signature, send the signed copy back. No third-party portal.
Syncthing: No.

Share linksZynk wins

Zynk: Yes.
Syncthing: No. Not a link product.

Drop linksZynk wins

Zynk: Yes.
Syncthing: No.

Recipient choiceZynk wins

Zynk: Recipient accepts and picks the device.
Syncthing: Sync replicates to every configured device. Deletions propagate without per-file consent.

CLIZynk wins

Zynk: Yes, anywhere you can open a terminal.
Syncthing: CLI available, but for managing sync folders, not sending files.

What we noted

Syncthing is a continuous folder-sync program, not a send product.
If what you want is folders that stay mirrored across your machines on their own, that's Syncthing's whole job, and Zynk doesn't do continuous sync. Zynk is for sending something on purpose, once, to a device you choose.