# Si4Keyboard

> Si4Keyboard (iPhone/iPad app by 文焕 陈.)

- Source: https://appshunter.io/ios/app/si4keyboard/id6745263713 (this page in markdown: same URL + `.md`)
- Developer: [文焕 陈](https://appshunter.io/developer/1810161184)
- Category: Utilities, Business
- Price: $0.99
- Age rating: 17+
- Requires: iOS 17.6 · 14 MB
- Languages: American English, Arabic, French (France), German (Germany), Japanese, Chinese (Simplified, China)
- Released: 2025-05-09
- Data updated: 2026-05-16
- User reviews in markdown: https://appshunter.io/ios/app/si4keyboard/id6745263713/reviews.md

## What is Si4Keyboard?

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.”


## Version history (last 4 releases)

### 1.5 — 2025-12-04

• **Keyboard Guide Feature** - New floating hint guide system to help users quickly learn keyboard usage. Interactive three-step guide covering key exchange, encryption, and decryption with automatic button highlighting and page navigation

• **Optimized Key Selection** - When only one public or private key is available, the system automatically selects it by default, simplifying the user experience especially for first-time users

• **Improved Key Selection UI** - Added select decryption private key functionality on the left side of keyboard for better accessibility and intuitive operation

• **Enhanced Short Link Messages** - Improved hint messages during short link generation process with better multilingual display support

• **Code Refactoring** - Refactored keyboard setup code structure for better maintainability and improved initialization flow

• **Bug Fixes** - Fixed multiple known issues, improved application stability, optimized code performance, and reduced memory usage

### 1.3 — 2025-12-02

- Added PGP encryption principles tutorial step with visual flow diagrams
- Added language selector on welcome page with real-time switching
- Optimized text display: left-aligned, increased line spacing
- Fixed return to onboarding feature, supports jumping to original step
- Removed "Got it" button, only kept return to onboarding
- Added encryption tutorial link in Settings page
- Added comprehensive multilingual translation support (6 languages)

### 1.2 — 2025-05-23

Did you know? PGP messages are often too long to send easily to friends. But Si4Key has introduced a creative solution—PGP Message Relay. It uploads your encrypted message to the cloud and gives you a short link. You can then share this link with your friends, allowing them to access the content.
Most importantly, you’re always in control—you can enable or disable this feature in settings.
Also, the message stored in the cloud is temporary—usually kept for only one hour, which greatly improves security.
You can easily send the short link via iMessage, making your conversations clear and concise.

### 1.0 — 2025-05-09

No release notes.

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## More apps by 文焕 陈

- [Si4iLocker](https://appshunter.io/ios/app/si4ilocker/id6747120411)

All apps by 文焕 陈: https://appshunter.io/developer/1810161184

## Related topics

[si4keyboard](https://appshunter.io/ios/topics/si4keyboard)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-05-16.*