Welcome to NooK! (No one Knows) [https://semweb.solutions/nook/]
Private Android SMS Messaging Powered by AES-256 Encryption
Secure. Simple. Offline.
NOOK transforms your everyday SMS into truly private conversations. Built directly on the cellular network, it requires to operate zero internet connection and collects/shares absolutely no data. Checks over the Internet for possible APK modifications using SHA release check. Your privacy isn't just a feature—it's the foundation.
✨ Why Choose NooK?
Military-Grade Encryption: Your messages are secured with AES-256 before they ever leave your device.
No Internet? No Problem: Communicate securely using the existing SMS infrastructure, even in areas with no data signal.
Your Data Stays Yours: We don't collect, store, or share anything. No trackers, no analytics, no cloud servers.
Open Source & Transparent: The entire codebase is public for anyone to audit. No secrets, no backdoors.
🚀 Quick Installation Guide from Android 8 (Oreo) on
Ready to take control of your SMS privacy? Getting started is easy.
Download the App
Download the latest NooK APK [https://semweb.solutions/nook/nook.apk] directly or from here in [https://github.com/redskate/nook/tree/master/app/releases]
Note: Due to its SMS permissions, NooK is 🚫 not available on the Google Play Store.
Thus: Enable Installation from Unknown Sources
On your Android device, go to Settings > Security.
In your device settings on privacy and security, enable the option "Install unknown apps" or "Allow from this source" or "disable APP block" for your file manager or browser (You may always enable that again after this installation).
NB: Android installer will want to "understand" that the APP be potentially dangerous
Well: maybe "potential-ly". But not dangerous at all -> see the code (SmsReceiver, SmsSender, SmsScanner) - NooK is safe.
💡 In the Warning Android Instalation Popup, CHOOSE "more details" and then CONFIRM (INSTALL) ANYWAY
🚀 Launch NooK APP
❗ READ and Accept disclaimer (!!) & Grant 3 Permissions
Open the downloaded APK file and follow the installation prompts.
When prompted, grant the necessary permissions (like SMS and contacts). These are required only for the app to function—to send, receive, and encrypt messages for your trusted contacts. We never misuse them.
Start Chatting Securely!
Open NooK, select a contact, make it to trusted contact, and set a shared secret (a password you both agree on). Share the secret by voice (more secure) or paper.
That's it! Your messages are now encrypted end-to-end.
You might see a cyclic warning from Google Play Protect or other virus scanners. This is a known false positive triggered by the app's access to SMS permissions.
Why this happens: Scanners often flag any app with SMS permissions as potential malware.
The Truth: NooK is 100% safe and open source - see yourself. It only sends an SMS when you press NooK's send button in one chat, stores all data encrypted on your phone and keeps them there.
Install with Confidence: A permanent notification reminds you the app is active and safe.
📖 First-Time User Tips
Set Up NooK App Lock: Immediately enable the fingerprint or PIN lock in settings to secure the app when you're away.
Share Secrets Safely: Agree on your shared passwords with contacts through a secure secondary channel (like a quick call or in person) before starting a conversation. However, due to the Default Base256 encryption set, you might also use NooK fresh created chat to agree on encryption / encoding passwords (use with parsimony).
Understand What's Visible: While your message content is encrypted, standard SMS metadata (like the sender's phone number and timestamp) remains visible to your cellular carrier—just like with any regular text message.
🚫 Important Notes
Android seems to restrict more and more the APPs registered by GOOGLE Play Store, the official APP store of GOOGLE for Android standard OS phones.
You might search in the refurbed market for a good pixel phone (my suggestion: pixel 5).
Here what you can do, in case you'd NEED NooK:
1. Look for and install other APP archives like F-DROID [https://f-droid.org] or AURORA [https://store.auroraoss.com]. You will have to search for their APK directly and install first the archive's APK or follow their instructions, then from there NooK (if present).
2. Consider using a phone with unlocked bootloader, install a custom ROM like lineage [https://lineageos.org/], e/OS [https://e.foundation/e-os/] or another one here: [https://keepandroidopen.org] and proceed with step 1.
3. Root your device and "de-google" it. Your device should belong to you. Note: Rooting may prevent you to use identity and banking APPs. Keep a second phone for safe communication only!
Currently to my knowledge the GOOGLE (!) pixel smartphones have an unlockable bootloader allowing to install a more freedom friendly custom ROM.
Welcome to a world where your conversations are truly your own. With NooK, No One Knows.