Ranking the Best and Worst Encrypted Messaging Apps.

The short answer: use Signal. It's secure, audited, free, and the people you message will actually install it. If metadata privacy is your priority — keeping who you talk to hidden, not just the message content — SimpleX Chat is the strictest option, with Session a more convenient step down. Everything that ties you to a phone number, or only encrypts one-to-one chats, leaks more than it protects.

That's the recommendation. The ranking below explains where each of the main apps lands and why, and the sections after it cover the parts a ranking alone misses: why the SMS you're replacing is so much worse than it looks, why some apps that advertise encryption barely deliver it, and why the app you install is only half the decision.

For a maintained side-by-side reference — encryption protocols, metadata practices, and exactly what each app hands over to law enforcement — see the companion encrypted messaging apps comparison. This page is the opinionated walkthrough; that one is the spec sheet.

The single most useful change most people can make is to stop using SMS for two-factor authentication and move those codes to an authenticator app. SMS 2FA is exactly what SIM swapping steals.

The ranking, worst to best

The apps below are judged on what actually determines privacy. Are all conversations end-to-end encrypted, not just one-to-one? Does the app force a real-world identifier like a phone number? How much metadata does it leak, is the infrastructure centralised, and is the code open to independent review? Usability counts too. The most secure app you won't use protects nobody.

7. WhatsApp

WhatsApp uses the Signal encryption protocol, which sounds reassuring and mostly isn't. Encryption of message content is not the same as privacy. As a Meta subsidiary it collects extensive metadata — your contacts, when and who you message, your usage patterns — and links it to a phone number and, often, a real Facebook identity. Content is encrypted; the map of your entire social graph is not. For anything sensitive, the metadata is the exposure, and WhatsApp leaks it by design.

6. Telegram

Telegram is a step up from WhatsApp in exactly one respect: it doesn't tie you to a Facebook profile. Everything else is weaker than its reputation. Its default chats are not end-to-end encrypted — only opt-in "Secret Chats" are, and group chats never are. It still requires a phone number, and its servers are centralised, so the metadata sits in one place a subpoena can reach. Fine for chatting with people who already have your number; not a privacy tool.

5. Signal

Signal is the mainstream recommendation for good reason: end-to-end encryption on everything including group chats, minimal metadata retention, fully open-source, and a real track record. Its historic weak point was the phone-number requirement, which leaked who-contacts-whom. That's largely been addressed. Signal added usernames and phone-number privacy in 2024, so your number is hidden from contacts by default, and the project has been working toward optional signup without a number at all. For most people, Signal is the right answer. It's secure, usable enough that non-technical contacts will actually adopt it, and transparent enough that experts can verify the claims.

4. Threema

Threema's distinguishing feature is that it never asks for a phone number — you get a random Threema ID, which cuts the biggest single source of metadata leakage. Content is strongly encrypted and the business functionality is solid. The tradeoff is centralised infrastructure: one globally accessible point for authorities to target. Good for identity-light everyday use; less ideal where you need resistance to a server being seized.

3. XMPP (with OMEMO)

XMPP is a protocol rather than a single app, which is the point. With the OMEMO extension for end-to-end encryption, optional anonymous account creation, and the ability to run your own server, it hands power users complete control over their infrastructure and data — including routing over Tor for metadata privacy. The cost is setup: it's the least beginner-friendly option here, and getting it right takes real technical effort.

2. Briar

Briar is built for the hardest case — communication when the internet is cut off or actively hostile. It's fully decentralised with no servers at all: devices sync directly over Bluetooth or Wi-Fi, and internet connections route through Tor. There's no central point to seize or observe, and it's open-source. That resilience comes at the price of usability — pre-arranged device pairing and a workflow optimised for high-risk situations make it a specialist tool, not a daily driver.

2. Session

Session is a strong balance of serious privacy and everyday usability. It uses no phone number or email — just a randomly generated account ID. Traffic routes through a decentralised onion network, so there's no central server holding metadata and no single location to subpoena. Messages are end-to-end encrypted. And because traffic is duplicated across a swarm of volunteer-run nodes, mass metadata collection is impractical. It supports multimedia and works across platforms without the specialist friction of Briar or XMPP. The one caveat: that account ID is still a long-term identifier, which is exactly what the app ranked above it does away with.

1. SimpleX Chat

SimpleX takes the metadata argument to its logical end: it has no user identifiers at all — no phone number, no username, not even a random account ID like Session's. Instead of routing messages to you, it routes them to disposable, per-contact message queues, a separate address for each person you talk to, rotated over time. The practical effect is that the servers never hold a list of who you are or who your contacts are, because that list doesn't exist in a form they can see. It's end-to-end encrypted, open-source, and can be fully self-hosted if you want to run your own servers. The tradeoff is usability: connecting means exchanging an invite link or QR code rather than looking up a username, and it's newer and less polished than Signal. But on the specific axis of who can see that you talked, to whom, and when, nothing mainstream beats it right now.

The honest summary: Signal for most people, because adoption matters and it's genuinely secure. SimpleX when metadata privacy is the absolute priority, with Session a slightly more convenient step down. Everything that requires a phone number leaks who you talk to even when the message content is safe, and anything that only encrypts one-to-one chats — WhatsApp, Telegram — isn't offering the protection its marketing implies.

Why SMS is the thing to leave behind

The reason any of this matters starts with what you're replacing. SMS was designed in the 1980s, long before anyone was defending against interception at scale, and it shows. Messages travel in plain text through your carrier's infrastructure, so anyone with access to the telecom network between sender and recipient can read them. That's not theoretical. Three attack types exploit it routinely:

• SIM swapping — an attacker social-engineers your carrier into moving your number to a SIM they control, then receives everything sent to it, including SMS two-factor codes. That's how account takeovers cascade from a single phone number.
• SMS spoofing — the sender number is trivially faked, which is the backbone of text phishing that appears to come from your bank.
• Network interception — flaws in the signalling between carriers let messages be read or redirected in transit.

The 2020 Twitter breach is the textbook case. Attackers used SMS-based social engineering to bypass two-factor authentication on high-profile accounts — Musk, Gates, Obama — and ran a cryptocurrency scam that netted around $120,000. Then, in late 2024, a telecommunications breach attributed to Chinese state hackers hit "highly targeted individuals." In response, the US Cybersecurity and Infrastructure Security Agency did something unusual: it told senior officials in writing to stop using SMS and switch to encrypted messaging like Signal. The FBI gave the same advice publicly around the same time. When the agencies whose job is protecting government communications say the default texting app isn't safe enough for the people they protect, it isn't safe enough for you either.

Not all "encrypted" is equal

A green padlock in an app's marketing doesn't mean the implementation holds up. Two cases make the point.

X (formerly Twitter) DMs added "end-to-end encryption," but the implementation has holes serious enough that security researchers won't endorse it for anything sensitive. X can replace a user's public key without notifying them — the exact capability that lets a provider quietly intercept messages, and something Signal alerts you to. There's no forward secrecy, so a single compromised key exposes the entire history rather than a slice of it. The code is closed and has had no external audit, and encryption is limited to paid, verified accounts who already follow each other. It's marginally better than plaintext DMs; it is not a private channel.

iMessage is a more interesting case, because Apple did real work here. Its PQ3 protocol added post-quantum cryptography. That's protection against an adversary who records your encrypted traffic today to decrypt later, once quantum computers are capable — "harvest now, decrypt later," which agencies are widely believed to be doing. PQ3 was a genuine advance. But Apple's launch framing kept positioning it as ahead of Signal, and that didn't age well. Signal had already shipped post-quantum key establishment (PQXDH). It has since gone further with a post-quantum ratchet, SPQR, making the ongoing key exchange quantum-resistant too, not just the initial handshake. The gap Apple claimed has closed.

The more durable point is the one the crypto comparison tends to bury: iMessage is closed-source, so you're trusting Apple's description of what it does rather than being able to verify it. And against a serious adversary, nobody breaks the encryption anyway — they compromise the device, the way Pegasus spyware has on iPhones. Post-quantum math on a proprietary platform you can't inspect is a strong wall on uncertain ground. Open-source, independently audited software is the thing that actually lets the claims be checked, which is why it keeps mattering more than any single protocol upgrade.

The app is only half the decision

Even the right app fails you if you install the wrong copy of it. There's a steady stream of trojanized messenger "mods" — fake versions of Signal and Telegram that carry spyware — and they reach official stores. Kaspersky found infected Telegram builds on Google Play aimed at Chinese and Uyghur users. Separately, researchers found a fake Telegram ("FlyGram") and a spoofed Signal ("Signal Plus Messenger") on Google Play and the Samsung store. Both carried the BadBazaar spyware, and both were attributed to a Chinese group called GREF. Signal Plus could silently link a victim's account to an attacker's device for live message interception. The builds look identical to the real thing — same branding, same working features — while quietly exfiltrating contacts, messages and files.

The defence is simple and worth stating as rules:

1. Install messaging apps only from the official source — the developer's own site or the primary app store listing — and never a "mod," "plus," or "optimised" version, however appealing the extra features sound.
2. Check the developer name and reviews before installing, and be suspicious of a familiar app published under an unfamiliar account.
3. Keep the app updated, and periodically review the linked devices / active sessions inside the app for anything you don't recognise.
4. Be sparing with permissions — a messenger doesn't need every grant it asks for.

And there's a piece no messaging app can solve: the phone itself. On a standard iPhone or Android, the device is logged into an Apple or Google ID at the OS level. That's the identity tying your activity together, whichever app you chat in. If your threat model is serious, the device and OS choices — up to a de-Googled Android like GrapheneOS — matter more than the messenger. One last thing while you're here: SMS 2FA is one of the weakest links in the whole chain. Move your two-factor codes into an authenticator app or your password manager's 2FA support, rather than leaving them in the text-message system this whole guide is about replacing.

Where this leaves you

So: Signal for most people, SimpleX or Session when metadata is the priority, and nothing that only encrypts one-to-one chats or ties you to a phone number. But the app is the easy part. Install the real version from the real source, treat any "encrypted" claim on closed, unaudited software as unverified rather than false, and remember that the identifier you hand over and the phone you run it on decide more about your privacy than the logo on the icon does.