CipherKey

CipherKey is an Android keyboard that encrypts your messages before you send them — inside WhatsApp, Telegram, Signal, Discord, SMS, email, or any other application with a text field.

You and your correspondent hold the same key. You compose a message, tap Encrypt, and send the result as you normally would. Their copy of CipherKey restores it. Everyone in between, including the messaging provider, sees only encrypted text.

CipherKey does not transmit anything itself and has no account, no sign-in and no server. It also never encrypts what you type unless you tap Encrypt — ordinary typing is unaffected.

A CAPABLE DAILY KEYBOARD
• Predictions and autocorrect designed to stay out of the way — what you typed stays one tap away
• A personal dictionary you can inspect, edit and delete in full
• Gesture typing, space-bar cursor control, swipe-to-delete
• English, Bengali and Hindi, with phonetic input and native-script layouts
• Emoji, kaomoji, symbols and an optional number row
• One-handed and floating layouts, adjustable key height and haptics
• Light and dark themes, custom key colours, and your own photograph as a background

ENCRYPTION
• One-tap encrypt and send, or encrypt first and review — configurable per application
• Undo immediately after encrypting
• Encrypt a selection or the entire field
• Automatic splitting of long messages for SMS

READING ENCRYPTED MESSAGES
• Decrypt from the keyboard, from your selection or the clipboard
• Decrypted text appears in the keyboard, never inserted into the conversation
• Automatic key selection — no need to track which key belongs to whom
• Paste an exported transcript and decrypt every message in it at once
• Save and search conversations, stored encrypted on the device

KEY MANAGEMENT
• Multiple keys, one per correspondent or context
• Share in person by QR code, or remotely under a passphrase
• Verify a key by short code or by reading a word list aloud
• Rotate keys without losing access to older messages
• Encrypted backup of every key under a passphrase you choose
• Lock keys behind your fingerprint or device PIN

PRIVACY
• Keys never leave the device. No account, no server, nowhere for messages to be held
• Password fields switch to a plain keyboard with no suggestions and no learning
• Clipboard history that refuses passwords and expires on a schedule you set
• Incognito mode suspends all learning
• No accessibility service and no notification access

OPTIONAL AI ASSISTANCE
CipherKey can rewrite, translate, summarise, draft replies and generate images using Google's Gemini. It is disabled until you supply your own Google API key, every request displays the exact text before anything is sent, encryption keys and encrypted messages are refused outright, and costs are billed to your own Google account.

BEFORE YOU BEGIN
Your keys exist only on your device. This is what makes the product private, and it means that losing the device without a key backup renders those messages permanently unreadable — by anyone, including the developer. Please use the encrypted key backup.

CipherKey uses established cryptography and publishes its message format for examination, but it has not been independently audited. Where disclosure would carry serious consequences, please use software that has.

This free version displays advertising on the settings screen and within the AI panel. There is none over the keys and none adjacent to what you are typing.