Private Chat is the messaging tab you reach for when you want to talk securely to another Fortress user. It is end-to-end encrypted, free on every tier, and visible only to the two phones in the conversation. Our servers route the ciphertext but cannot read it.
What Private Chat is
Two short answers:
- For the user: the messaging app inside Fortress Communicator that you use to talk to other Fortress users. Not SMS. Not iMessage. A separate channel.
- For the curious: an in-app messaging system where every message is encrypted with a key only your phone and the other person’s phone hold. Our servers deliver the message; they cannot read the content.
The green banner
Every Private Chat thread shows a green banner at the top that reads End-to-end encrypted. That banner is your visual confirmation that you are in Private Chat — not in SMS, not in a group chat that has been mirrored to your phone for convenience. When you see the green banner, only the two endpoints can read what is being typed.
If you ever see a Private Chat thread without the banner, stop and email support@fortressdms.com. That should not happen.
One-to-one and group Private Chat
Both are supported:
- One-to-one — start from any Fortress contact in the Directory. Tap their name, then the message icon. The thread you land in is a Private Chat by default.
- Group — from the Private Chat tab, tap the + in the upper right, then pick the Fortress users to add. The group is end-to-end encrypted as well; each new message is encrypted to every member’s device.
There is no participant cap that matters in practice. We have tested groups up to several dozen people without issue.
Private Chat vs SMS / MMS
This is the distinction that matters most. They look similar in the app — both are message threads — but the network underneath is completely different:
| Private Chat | SMS / MMS | |
|---|---|---|
| Who you can message | Other Fortress users only | Anyone with a phone number |
| Encryption | End-to-end | Carrier-encrypted in transit only |
| Network | Fortress (SignalR) | Telnyx + carrier (PSTN) |
| Cost | Free, on every tier | Counts against your SMS / MMS bundle |
| Server can read it | No (ciphertext only) | Yes (the carrier needs to) |
| Group support | Yes | Yes |
| 10DLC / TCR rules apply | No | Yes (business SMS) |
Real-time delivery
Private Chat messages travel over our SignalR push channel. Delivery latency is typically a fraction of a second on Wi-Fi or LTE. If the recipient is offline, the encrypted message queues until their next sign-in and then delivers.
What Fortress sees
On the server side we see only ciphertext — the encrypted blob of your message — plus the routing metadata required to deliver it (which account is sending, which account is receiving, what time the message arrived). We do not see who you talked about or what you said. A subpoena against Fortress for the content of a Private Chat message yields the encrypted blob; we have no key to decrypt it.
We do retain the routing metadata for billing reconciliation, spam-prevention, and compliance with lawful process. The metadata cannot reveal message content.
What Private Chat cannot do
- Message non-Fortress users. The encryption relies on both endpoints running the Fortress app and holding a Fortress identity key. If you need to text someone outside Fortress, use the Messages tab (SMS / MMS).
- Replace your phone’s carrier messaging. Texts from your bank, your doctor’s appointment reminders, and two-factor authentication codes still arrive on your phone’s regular Messages app — not in Fortress.
- Provide forward secrecy yet. This is version 1 of the protocol. If an adversary captures your device’s identity key today, every prior Private Chat encrypted to that key could theoretically be decrypted. Forward secrecy (a continuous key ratchet that retires old keys) is on the roadmap.
We’ve been burned before by staff using personal apps like WhatsApp for shift-to-shift communication, so this is something our command staff has been asking about for a while. Quick question — does the message history persist on the device after a user’s account is deactivated, or does it wipe automatically? That’s going to be a big compliance question for us before we can roll it out.
We’ve been burned before by staff using personal apps to coordinate shift stuff, so anything that keeps those conversations on a secured platform is a win in my book. Quick question though — does Private Chat log message metadata (timestamps, sender IDs) for internal audit purposes, or is it truly invisible to admins as well? That distinction matters a lot when it comes to grievance investigations.
We switched to something similar about eight months ago and the difference in how staff communicate sensitive inmate info is night and day — no more worrying about personal texts being subpoenaed or ending up on the wrong device. Quick question though: does your system log metadata like timestamps and sender IDs for internal audit purposes, even if the message content itself is encrypted? That’s been a sticking point with our compliance officer.
We’ve been burned before by staff using personal apps to coordinate on sensitive matters, so this kind of in-network encrypted chat is exactly what we’ve been pushing for. Quick question though — does the message history get purged automatically after a set period, or does admin have control over retention settings? That piece matters a lot for our compliance folks.
We switched to this about four months ago and the difference in communication speed during shift handoffs has been noticeable — no more worrying about sensitive inmate info going through regular text threads. One question though: does the system log message metadata (timestamps, sender IDs) for audit purposes even if the content itself stays encrypted?
We’ve been burned before by staff using personal texting apps to coordinate shift coverage and it created a real headache during an internal review. Does Private Chat keep message logs accessible to administrators for compliance purposes, or is it strictly end-to-end with no admin visibility at all? That distinction matters a lot for us before we push this to the whole floor.