AI Writing Assistant Keyboard for iOS | KeyboardAi

AI-Powered iOS Keyboard Extension that improves your writing with GPT-4o-mini in real-time. Enhance grammar, style, and clarity directly in any iOS app - Messages, Mail, Notes, and more.

Keywords: AI Writing Assistant, iOS Keyboard Extension, GPT-4 Keyboard, AI Text Enhancement, Grammar Correction iOS, Writing Improvement Tool, OpenAI Keyboard, Smart Keyboard iOS, AI Content Generator, Real-Time Text Processing

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Table of Contents

• Overview
• Features
• Security & Privacy
• Requirements
• Quick Setup
• Enable the Keyboard
• Usage
• Architecture
• Technical Details
• Troubleshooting (FAQ)
• Roadmap
• License & Credits

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Overview

KeyboardAi is an advanced AI-powered iOS keyboard extension that revolutionizes your mobile writing experience. Using OpenAI's GPT-4o-mini, this intelligent keyboard rewrites and refines your text in real-time to make it clearer, more correct, and more natural - all without leaving your current app.

Perfect for:

• Content creators writing social media posts
• Professionals crafting emails and messages
• Students improving academic writing
• Anyone who wants better grammar and clarity on iOS

Technical Requirements: iOS 15+ (streaming support). iOS < 15 supported with non‑streaming mode.

Features

AI-Powered Writing Enhancement

• ✨ Improve Writing: One-tap AI grammar correction and style enhancement
• 📝 Make Shorter: AI text summarization maintaining core meaning
• 📄 Make Longer: AI content expansion with smooth transitions
• ⚡ Real-Time Streaming: Live preview with GPT-4o-mini powered suggestions
• 🔄 Smart Actions: Replace, Insert, or Copy AI-generated text
• 🎯 Context-Aware: Reads surrounding text for better AI suggestions
• 📱 Universal iOS Support: Works in Messages, Mail, Notes, Safari, and all iOS apps
• 🎨 Modern UI: Clean design with status indicators and haptic feedback

Security & Privacy

Privacy-First AI Keyboard Design - Your data security is our priority:

• 🔐 Secure API Key Storage: OpenAI API keys stored in iOS Keychain (military-grade encryption)
• 🛡️ App Group Isolation: Secure data sharing via group.tye.KeyboardAi
• 🚫 No Data Collection: Zero built-in analytics or tracking
• 🔒 HTTPS Only: All API requests encrypted end-to-end
• ✅ User Control: Text sent to OpenAI only when you explicitly trigger AI actions
• 📝 Open Source: Full transparency - inspect the code yourself

Requirements

1. OpenAI account and API key (credits required)

2. Xcode capabilities for app/extension sharing:

• App Groups: group.tye.KeyboardAi on targets KeyboardAi and KeyboardExtension
• Keychain Sharing: same access group on both targets

Quick Setup

open KeyboardAi.xcodeproj  # open the project in Xcode

In the KeyboardAi app:

• Enter your API key (sk-…)
• “💾 Save API Key”, then “🧪 Test API Key”

Enable the Keyboard

1. iOS Settings → General → Keyboard → Keyboards → Add New Keyboard…
2. Choose “KeyboardExtension”
3. Enable “Allow Full Access” (required for networking)

Usage

1. Place the cursor in any app (Notes, Mail, Messages…)
2. Switch to the “KeyboardExtension” keyboard (globe 🌐)
3. Type your text, then choose an action:
   • ✨ Improve Writing → corrects and improves
   • Make Shorter → makes it more concise
   • Make Longer → expands the idea
4. Preview live, then choose Replace, Insert, or Copy

Quick examples:

Improve   : i want go to store today maybe buy some thing
→ I want to go to the store today to maybe buy something.

Shorten   : In light of the fact that we are running behind schedule
→ We’re running behind schedule.

Lengthen  : The meeting was productive
→ The meeting was productive, covering our key milestones and clarifying next steps with clear owners and deadlines.

Architecture

Views and Styling (new layout)

KeyboardExtension/
 ├─ Views/
 │  ├─ KBColor.swift                 # Centralized palette (tileBG, midGreyText…)
 │  ├─ KeyboardHomeStyling.swift     # Home styling (Improve + Shorten + Lengthen)
 │  ├─ KeyboardControlsView.swift    # Home (buttons, status, bottom bar)
 │  ├─ BottomActionBarView.swift     # Bar [space | delete | return]
 │  └─ ImproveWritingView.swift      # AI preview (stream + Insert/Replace/Copy/Refresh/Back)
 ├─ Prompts/
 │  ├─ ImprovePrompt.swift           # System prompt for improvement
 │  ├─ ShortenPrompt.swift           # System prompt for shortening
 │  └─ LengthenPrompt.swift          # System prompt for lengthening
 ├─ KeyboardViewController.swift     # Orchestration + wiring of actions
 ├─ TextProxyBestEffort.swift        # Full read via proxy (scan + probes)
 └─ OpenAIService.swift              # SSE streaming (iOS 15+) + fallback

Xcode tip: if you see greyed‑out files after this move, drag‑drop the Views/ folder into the KeyboardExtension target to refresh references.

KeyboardAi/
├─ KeyboardAi/                     # Host application (API key, test, guides)
│  ├─ ViewController.swift         # Configuration UI + API test
│  ├─ KeychainHelper.swift         # Secure storage (Keychain + App Group)
│  └─ OpenAIService.swift          # App: non‑streaming requests
│
└─ KeyboardExtension/              # Keyboard extension
   ├─ KeyboardViewController.swift # UI orchestration + logic
   ├─ Views/…                      # Views and styling (see above)
   ├─ Prompts/…                    # System prompts (Improve/Shorten/Lengthen)
   ├─ TextProxyBestEffort.swift    # Read “all accessible text”
   └─ OpenAIService.swift          # Extension: streaming requests (iOS 15+)

Technical Details

• OpenAI model: gpt-4o-mini (fast/cost‑effective), temperature = 0.3
• SSE streaming on the extension (non‑streaming fallback for iOS < 15)
• Large input budget (≈ 10,000 tokens, ≈ 40,000 characters)
• “Best‑effort select all”: reads all accessible context without altering the document
• OpenAIService with PromptKind (improve|shorten|lengthen) and modular prompts
• Replace/Insert via textDocumentProxy; Copy and Refresh in the preview

iOS limitations to know

• Keyboards cannot officially select text: reading is via before/after context
• Network access requires “Allow Full Access”
• Text after the cursor may be inaccessible depending on the host app

Troubleshooting (FAQ)

• “API key not configured” → Save the key in the app, verify App Group + Keychain Sharing
• “No text to improve” → Type some text and ensure the cursor follows the text
• “Network request failed” → Enable Full Access, check your connection and key

Debug tip:

// In the extension
print("[KeyboardAI] captured=\(capturedText.count)")
print("[KeyboardAI] improved=\(improvedText.count)")

Roadmap

• Writing styles (formal, concise, friendly…)
• Multiple suggestions with user choice
• Keyboard shortcuts and UI customization
• Local history + quick copy
• Streaming with progressive indicators

License & Credits

Educational sample project. Use it freely to learn and build your ideas. Created by Sanz (October 31, 2025).

Note: Respect OpenAI’s policies and never share an API key publicly.