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Si4Key: Secure Your Input, Empower Your Identity
Si4Key is a privacy-first companion keyboard designed to enhance your existing input method with seamless local encryption, one-tap digital signature, and offline key management.
Whether you’re sending private messages, signing documents, or inputting sensitive data, Si4Key ensures that every keystroke stays secure — without changing how you type.
Key Features:
• Local-first encryption — your input never leaves your device
• Built-in support for OpenPGP/GPG digital signatures
• Offline key storage — no cloud syncing, you’re in full control
• Minimal and intelligent design — easy to use, smart when needed
• Supports multiple languages with future-ready architecture
Why Si4Key?
Because your input method deserves the same level of protection as your data. Si4Key doesn’t replace your keyboard — it strengthens it.
“Typing should be private. Signing should be simple. Si4Key makes both possible.”