NexLink replaces your default Android SMS/MMS app, gathers your social-app notifications
into a single unified inbox, and encrypts NexLink-to-NexLink conversations end-to-end —
with no servers, no analytics, and no tracking. Everything runs on your device.
Features
- Unified inbox — SMS, MMS and social notifications in one chronological list.
- End-to-end encryption — NexLink↔NexLink messages encrypted on-device; your carrier only sees ciphertext.
- Calls & voice — native call handling plus recorded voice messages.
- Wear OS companion — read and reply from a paired watch.
- Media & camera — attach gallery photos or snap a new one in-chat.
- No backend — no server, no SDKs, no ads.
One inbox for
SMS / MMS · Signal · WhatsApp · Telegram · Messenger (social notifications are mirrored read-only — nothing leaves your device).
Encryption
When both parties use NexLink, messages are automatically encrypted on-device:
| Stage | Algorithm |
|---|
| Key exchange | Elliptic-curve Diffie-Hellman (ECDH), curve P-256 |
| Session key | SHA-256 of the ECDH shared secret |
| Message | AES-256-GCM, random 96-bit IV per message |
Encrypted messages are stored as ciphertext ([NXMSG1:…]). Only NexLink can decrypt them.
Current limitation: static identity keys (no Double Ratchet / forward secrecy). Per-session ephemeral keys are planned.
Modules
| Path | What it is |
|---|
app/ | Main Android application |
wear/ | Wear OS companion |
shared/ | Shared code / Data Layer contract |
android-app/ | Android app resources |
Privacy
NexLink collects no personal data and operates no servers. See the full
Privacy Policy (also hosted at
thvjq.com.au/nexlink/privacy).
Build
Standard Gradle project:
./gradlew assembleDebug
License
See LICENSE.
NexLink Social lives elsewhere
The encrypted messenger companion moved to
THVjQ/NexLink-Social on
2026-09-21, along with its specification, server infrastructure and the legal
pack it ships.
This repository is NexLink itself: :app, :shared and :wear. The two apps
never shared code — :app and :wear depend only on :shared — so the split
removed nothing either of them used.
The legal documents covering all four NexLink products, in English and
German, are published at https://thvjq.com.au/nexlink/legal/terms/ and
maintained in the Social repository, because the Social app is what ships them
inside an APK.
