No. Signal uses the Signal Protocol — a different cryptographic design built around the Double Ratchet algorithm, X3DH key agreement, and sealed sender metadata protection. It is not OpenPGP and is not compatible with PGP tools. Signal is purpose-built for messaging; OpenPGP is general-purpose encryption.

Is Signal more secure than PGPony?

For its specific use case (real-time messaging between two people who both use Signal), the Signal Protocol provides security properties OpenPGP does not — forward secrecy (a compromised key today doesn't decrypt yesterday's messages), break-in recovery, and protected metadata via sealed sender. For OpenPGP's use cases (anything outside a real-time chat between two Signal users), Signal cannot help. They protect different things.

Can I use PGPony inside Signal?

Technically yes — Signal carries text and files, so you could send a PGP-encrypted blob through Signal. But that would be wrapping one strong encryption layer inside another with no real added security, since Signal already encrypts end-to-end. The point of PGPony is to encrypt content for channels where Signal isn't available — email, SMS, code review, paste sites, archived files.

Why use PGPony if Signal exists?

Because Signal only works inside Signal. If you need to send something encrypted via email, SMS, Slack DM, a code comment, a paste site, an Apple Note, an archive shared via cloud storage, or any other non-Signal channel, you need a tool that produces ciphertext you can put anywhere. PGPony does that; Signal doesn't.

Does Signal require a phone number?

Signal historically required a phone number tied to your Signal account, though usernames now allow you to be reachable without sharing your number with everyone. PGPony requires no phone number, no account, no identifier of any kind — just an OpenPGP key you generate locally.

What about Signal's sealed sender vs PGP metadata?

Signal's sealed sender hides the sender identity from Signal's own servers in transit. OpenPGP does not have a built-in metadata protection layer — encrypted PGP messages reveal recipient key IDs by default, and PGPony does not implement OpenPGP's wildcard / hidden-recipient extension. For metadata-sensitive use cases, Signal's design is stronger.

Should everyone just use Signal?

For chat between two phones owned by two living humans, yes — Signal is the right tool and the OpenPGP world generally agrees on this. But that's a small slice of "things that need to be encrypted." Files at rest, email, archived material, communications with people not on Signal, content traveling across systems and over time — all of that is OpenPGP's territory.

// pgpony vs signal

PGPony vs Signal.

Signal is the best secure messenger ever built. We mean that — there\'s no diplomatic hedging here. But Signal and PGPony solve different problems. Signal is for real-time chat between two people who both use Signal. PGPony is OpenPGP encryption for everything that doesn\'t fit in a Signal conversation. Different tools, different jobs.

// the short version

Use Signal for chat. For two-way conversations between phones, Signal is unmatched. Use PGPony for everything else. Encrypted email, encrypted files, encrypted notes, encrypted anything that has to travel through channels Signal doesn\'t reach. They aren\'t substitutes — they\'re different categories.

What each one actually does.

Signal is an encrypted messaging app. It runs the Signal Protocol — a sophisticated cryptographic design with forward secrecy, break-in recovery, post-compromise security, and metadata protection (sealed sender). It works only inside Signal itself. To talk to someone, both of you must be running Signal.

PGPony is an OpenPGP encryption app. It produces standalone ciphertext blobs that you can put anywhere — in an email, in a text file, in a paste site, in a Git commit message, in a backup archive, on a USB drive in 2050. The recipient decrypts using their OpenPGP key, in whatever OpenPGP-capable software they prefer.

The cleanest test for which one you need: where does the encrypted content have to live? If the answer is "in a Signal conversation between me and one specific person right now," use Signal. If the answer is anywhere else — email, file storage, version control, SMS, paper printout, archive you\'ll open in five years — use PGPony.

At a glance.

	PGPony	Signal
Category	OpenPGP encryption app	Encrypted messenger
Crypto protocol	OpenPGP (RFC 4880, 9580)	Signal Protocol (X3DH + Double Ratchet)
Channels	Any — email, SMS, file, paste	Signal only
Real-time chat	No	Yes — that\'s its job
Forward secrecy	Not built-in to OpenPGP	Yes — Double Ratchet
Metadata protection	None built-in to OpenPGP	Sealed sender by default
Encrypts arbitrary files	Yes — any file, any size, any channel	Attachments inside Signal only
Encrypts text for non-app channels	Yes	No — chat only
Long-term archived ciphertext	Yes — designed for it	No — Signal messages aren\'t portable artifacts
Phone number required	No	Yes (usernames optional but account is phone-bound)
Account required	No	Yes
Works with any OpenPGP user	Yes	Both ends must be on Signal
Audited cryptography	OpenPGP standardized + library audits	Extensively peer-reviewed
Open source	Proprietary; uses audited open libs	Fully open source

Honest tradeoffs.

Where Signal wins

Forward secrecy. Signal\'s Double Ratchet means each message uses a fresh key. If your phone is compromised today, an attacker still can\'t read messages from last week. OpenPGP doesn\'t have this — a stolen private key decrypts every past message encrypted to it. For ephemeral chat, this matters a lot.
Metadata protection. Sealed sender hides who\'s talking to whom from Signal\'s servers. OpenPGP messages typically reveal recipient key IDs (and the sender via the signature). For metadata-sensitive use, Signal is structurally stronger.
The UX of a real chat app. Signal is a chat app, with chat-app UX — read receipts, typing indicators, disappearing messages, voice calls, video calls, group chats. PGPony is not trying to be that and would do it badly if it tried.
Massive user base. Signal has hundreds of millions of installs. There\'s a real chance the person you want to message already has it. PGPony users are a much smaller community, and the people you want to reach via PGP usually have to install something.
Free and fully open source. Signal\'s entire stack — client, server, protocol — is open source under permissive licenses, with extensive academic review of the protocol design itself.
It just works. No keys to exchange, no fingerprints to verify (though you can), no concept of "import a public key." Two people install Signal, they can chat. The friction floor for end-to-end encryption is essentially zero.

Where PGPony wins

It works in any channel. Email, SMS, Slack, Discord, code review tools, paste sites, file shares, Git commits, archive volumes. Signal works in exactly one place: Signal. If the encrypted content needs to live anywhere else, PGPony is the answer.
Files of any size, anywhere. PGPony encrypts a file once and produces a .pgp blob you can email, upload, store, hand-deliver on a USB drive. Signal\'s attachment story is "send through Signal", with size limits and the implicit assumption the recipient is in the conversation right now.
Long-term archival encryption. Encrypt a file with PGPony today, decrypt it in 2050 with whatever OpenPGP tool exists then. The standard is stable, ciphertext is portable, no service has to still exist. Signal is not for archive material — messages are tied to your Signal account and apps.
No phone number, no account. PGPony has no concept of an account, no servers tied to your identity, no phone number to publish. Signal requires a phone number at minimum (usernames let you stay reachable without sharing it, but the account is still phone-bound).
Works with anyone using OpenPGP. The recipient just needs any OpenPGP tool — GPG Suite, OpenKeychain, Mailvelope, FlowCrypt, GnuPG on Linux, anything. Signal requires both parties to install Signal.
Encryption with a paper trail. PGP signatures are persistent, portable, verifiable forever. A signed message from 2026 stays verifiable in 2046, by anyone, anywhere. Signal\'s authentication is ephemeral by design — strong in the moment, not designed to leave the conversation.
Different threat model fits different lives. A journalist receiving long-term archived source material wants OpenPGP. A developer signing a software release wants OpenPGP. Two friends chatting tonight want Signal. None of this is a contest; it\'s coverage.

When you want both.

Most security-conscious users end up with both apps installed, used for what each one does best. A practical taxonomy:

Real-time chat with another person who has Signal: Signal.
Real-time chat with a small group: Signal group.
Voice or video call you want encrypted: Signal.
Encrypted email to anyone with a published PGP key: PGPony.
Encrypting a file before uploading to Dropbox / Drive / S3: PGPony.
Signing a software release or Git tag: PGPony (or GnuPG on desktop with the same key).
Sharing a password or recovery code with one person, durably: PGPony.
Sharing the same with one person, ephemerally: Signal with disappearing messages on.
Archiving sensitive material for long-term storage: PGPony.
Communicating with someone who refuses to install Signal but does have PGP: PGPony.

There\'s no overlap that creates real conflict. The two apps live in different parts of your stack and don\'t compete for the same task.

One thing OpenPGP could learn from Signal — and is.

Signal\'s forward secrecy is genuinely better than what classic OpenPGP offers. The OpenPGP community is aware of this gap. OpenPGP v6 (RFC 9580) adds infrastructure for ephemeral subkeys and improved key rotation, and there\'s ongoing work on extensions for chat-like usage patterns.

That said: OpenPGP isn\'t trying to be Signal. The design tradeoff is intentional. OpenPGP messages are meant to be archivable, verifiable years later, decryptable with the same key for as long as you hold it. Forward secrecy is incompatible with that, by definition. The two designs serve different use cases by choice, not by accident.

The verdict.

Use Signal for Day-to-day chat. Voice calls. Video calls. Anything between two living humans on phones, in real time, where both parties are willing to install Signal. There is no better choice for this category.
Use PGPony for Encrypted email. Encrypted files. Encrypted notes. Encrypted backups. Encrypted communication with anyone who has a PGP key but not Signal. Long-term archived material. Software release signing. Code commit signing. Anything where the encrypted content has to travel through channels Signal doesn\'t reach, or live longer than a single conversation.
Use both Most people who care about end-to-end encryption end up using both, each for what it\'s good at. They aren\'t in competition — they cover non-overlapping problems.

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