SwiftSlate

System-wide AI text assistant for Android — powered by Gemini and custom providers

Type a trigger like ?fix at the end of any text, in any app, and watch it get replaced with AI-enhanced content — instantly.

     

Note

SwiftSlate works everywhere — WhatsApp, Gmail, Twitter/X, Messages, Notes, Chrome, and every other app with a text field. No copy-pasting. No app switching. Just type and go.

📋 Table of Contents

• Quick Demo
• Features
• Built-in Commands
• Getting Started
• How It Works
• Custom Commands
• API Key Management
• App Screens
• Privacy & Security
• Tech Stack
• Building from Source
• Contributing
• License

⚡ Quick Demo

📝  You type       →  "i dont no whats hapening ?fix"
⏳  SwiftSlate      →  ◐ ◓ ◑ ◒  (processing...)
✅  Result         →  "I don't know what's happening."

📝  You type       →  "hey can u send me that file ?formal"
⏳  SwiftSlate      →  ◐ ◓ ◑ ◒  (processing...)
✅  Result         →  "Could you please share the file at your earliest convenience?"

📝  You type       →  "Hello, how are you? ?translate:es"
⏳  SwiftSlate      →  ◐ ◓ ◑ ◒  (processing...)
✅  Result         →  "Hola, ¿cómo estás?"

✨ Features

🌐 Works Everywhere Integrates at the system level via Android's Accessibility Service. Works in any app — messaging, email, social media, notes, browsers, and more. ⚡ Instant Inline Replacement Type, trigger, done. The AI response replaces your text directly in the same field — no copy-pasting, no app switching. A spinner (◐ ◓ ◑ ◒) shows progress. 🔑 Multi-Key Rotation Add multiple API keys for automatic round-robin rotation. If one key hits a rate limit, SwiftSlate seamlessly switches to the next. 🌙 AMOLED Dark Theme Pure black (#000000) Material 3 interface designed for OLED screens — saves battery and looks stunning.

🤖 Powered by Gemini & Custom Providers Ships with Google's Gemini API (gemini-2.5-flash-lite, gemini-3-flash-preview, or gemini-3.1-flash-lite-preview). Or connect any OpenAI-compatible endpoint — use your own provider, model, and base URL. 🎨 Custom Commands Create your own trigger → prompt pairs. Define ?poem to turn text into poetry, ?eli5 to simplify for a five-year-old, or anything you can imagine. 🔒 Encrypted Key Storage API keys are encrypted with AES-256-GCM using the Android Keystore. Your keys never leave your device unencrypted. 🛡️ Privacy-First No analytics. No telemetry. No intermediary servers. Text is sent directly to the configured provider's API and only when a trigger is detected.

🧩 Built-in Commands

SwiftSlate ships with 9 commands plus dynamic translation — ready to use out of the box:

Trigger	Action	Example
?fix	Fix grammar, spelling & punctuation	i dont no whats hapening → I don't know what's happening.
?improve	Improve clarity and readability	The thing is not working good → The feature isn't functioning properly.
?shorten	Shorten while keeping meaning	I wanted to let you know that I will not be able to attend the meeting tomorrow → I can't attend tomorrow's meeting.
?expand	Expand with more detail	Meeting postponed → The meeting has been postponed to a later date. We will share the updated schedule soon.
?formal	Rewrite in professional tone	hey can u send me that file → Could you please share the file at your earliest convenience?
?casual	Rewrite in friendly tone	Please confirm your attendance at the event → Hey, you coming to the event? Let me know!
?emoji	Add relevant emojis	I love this new feature → I love this new feature! 🎉❤️✨
?reply	Generate a contextual reply	Do you want to grab lunch tomorrow? → Sure, I'd love to! What time works for you?
?undo	Restore text from before the last replacement	Reverts to your original text before AI modified it
?translate:XX	Translate to any language	Hello, how are you? ?translate:es → Hola, ¿cómo estás?

🌍 Supported language codes for translation

Use any standard language code with ?translate:XX:

Code	Language	Code	Language	Code	Language
es	Spanish	fr	French	de	German
ja	Japanese	ko	Korean	zh	Chinese
hi	Hindi	ar	Arabic	pt	Portuguese
it	Italian	ru	Russian	nl	Dutch
tr	Turkish	pl	Polish	sv	Swedish

…and many more. Any language code recognized by Google Translate works.

🚀 Getting Started

Prerequisites

Requirement	Details
Android Device	Android 6.0+ (API 23 or higher)
API Key	Free Gemini key at aistudio.google.com, or a key from any OpenAI-compatible provider

Installation

Tip

The APK is only ~1.3 MB — lightweight with zero external dependencies for networking or JSON.

1. Download the latest APK from the Releases page

2. Install the APK on your device (allow installation from unknown sources if prompted)

3. Open SwiftSlate and follow the setup below

Setup in 3 Steps

Step 1 🔑 Add API Key Open the Keys tab, enter your API key. It's validated before saving. Add multiple keys for rotation.

Step 2 ♿ Enable Service On the Dashboard, tap "Enable" → find "SwiftSlate Assistant" in Accessibility Settings → toggle it on.

Step 3 ✍️ Start Typing! Open any app, type your text, add a trigger like ?fix at the end, and watch the magic happen.

⚙️ How It Works

flowchart TD
    A["📝 You type: 'Hello wrld, how r u ?fix'"] --> B{"🔍 Accessibility Service\ndetects trigger"}
    B --> C["✂️ Extracts text before trigger:\n'Hello wrld, how r u'"]
    C --> D["🔑 Selects next available\nAPI key (round-robin)"]
    D --> E["🤖 Sends text + prompt\nto AI provider"]
    E --> F["⏳ Shows inline spinner\n◐ ◓ ◑ ◒"]
    F --> G["✅ Replaces text in-place:\n'Hello world, how are you?'"]

    style A fill:#1a1a2e,stroke:#e94560,color:#fff
    style B fill:#1a1a2e,stroke:#0f3460,color:#fff
    style C fill:#1a1a2e,stroke:#0f3460,color:#fff
    style D fill:#1a1a2e,stroke:#0f3460,color:#fff
    style E fill:#1a1a2e,stroke:#0f3460,color:#fff
    style F fill:#1a1a2e,stroke:#e94560,color:#fff
    style G fill:#16213e,stroke:#00b894,color:#fff

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🔧 Technical deep-dive

1. Event Listening — SwiftSlate registers an Accessibility Service that listens for TYPE_VIEW_TEXT_CHANGED events across all apps
2. Fast Exit Optimization — For performance, it first checks if the last character of typed text matches any known trigger's last character before doing a full scan
3. Longest Match — When a potential match is found, it searches for the longest matching trigger at the end of the text
4. Text Extraction — The text before the trigger is extracted and paired with the command's prompt
5. API Call — The text + prompt is sent to the configured AI provider using the next available key in the round-robin rotation
6. Inline Spinner — While waiting for the response, a spinner animation (◐ ◓ ◑ ◒) replaces the text to provide visual feedback
7. Text Replacement — The AI response replaces the original text using ACTION_SET_TEXT
8. Fallback Strategy — If ACTION_SET_TEXT fails (some apps don't support it), SwiftSlate falls back to a clipboard-based paste approach

🎨 Custom Commands

Go beyond the built-ins — create your own trigger → prompt pairs in the Commands tab.

How to Create One

1. Open the Commands screen
2. Enter a Trigger (e.g., ?poem)
3. Enter a Prompt — the instruction sent to the AI
4. Tap "Add Command"

Example Ideas

Trigger	Prompt	Use Case
?eli5	Explain this like I'm five years old and return ONLY the modified text.	Simplify complex topics
?bullet	Convert this text into bullet points and return ONLY the modified text.	Quick formatting
?headline	Rewrite this as a catchy headline and return ONLY the modified text.	Social media posts
?code	Convert this description into pseudocode and return ONLY the modified text.	Developer shorthand
?tldr	Summarize this text in one sentence and return ONLY the modified text.	Quick summaries

Important

Always include "return ONLY the modified text" in your prompt to ensure clean output without extra commentary from the AI.

🔑 API Key Management

SwiftSlate supports multiple API keys with intelligent rotation:

Feature	Details
Round-Robin Rotation	Keys are used in turn to spread usage evenly across all configured keys
Rate-Limit Handling	If a key gets rate-limited (HTTP 429), SwiftSlate tracks the cooldown and skips it automatically
Invalid Key Detection	Keys returning 403 errors are marked invalid and excluded from rotation
Encrypted Storage	All keys encrypted with AES-256-GCM via Android Keystore before being saved locally

Tip

Adding 2–3 API keys helps avoid rate limits during heavy use. Each API key has its own quota.

🖥️ App Screens

SwiftSlate has four screens accessible via the bottom navigation bar:

📊 Dashboard Service status indicator (green/red) Enable/disable toggle API key count Quick-start guide

🔑 Keys Add new keys (validated live) Delete existing keys AES-256-GCM encryption Multi-key management

📝 Commands 9 built-in commands (read-only) Add custom commands Delete custom commands Trigger + prompt pairs

⚙️ Settings Provider selection Google Gemini (default) Custom (OpenAI Compatible) Gemini model picker gemini-2.5-flash-lite (default) gemini-3-flash-preview gemini-3.1-flash-lite-preview Custom endpoint URL & model name

🔒 Privacy & Security

Note

SwiftSlate is built with privacy as a core architectural principle, not an afterthought.

	Concern	How SwiftSlate Handles It
👁️	Text Monitoring	Only processes text when a trigger command is detected at the end. All other typing is completely ignored.
📡	Data Transmission	Text is sent only to the configured AI provider (Google Gemini or your custom endpoint). No other servers are ever contacted.
🔐	Key Storage	API keys are encrypted with AES-256-GCM using the Android Keystore system before being saved locally.
📊	Analytics	None. Zero telemetry, zero tracking, zero crash reporting.
📖	Open Source	The entire codebase is open for inspection under the MIT License.
🔑	Permissions	Only requires the Accessibility Service permission — nothing else.

🏗️ Tech Stack

Language	Kotlin 2.1
UI	Jetpack Compose · Material 3
Navigation	Navigation Compose
Async	Kotlin Coroutines
HTTP	HttpURLConnection (zero external dependencies)
JSON	org.json (Android built-in)
Storage	SharedPreferences (encrypted via Android Keystore)
Core Service	Android Accessibility Service
Build System	Gradle with Kotlin DSL
Java Target	JDK 17
Min SDK	API 23 (Android 6.0)
Target SDK	API 36

Zero third-party dependencies for networking or JSON parsing — SwiftSlate uses only Android's built-in APIs.

🔨 Building from Source

Prerequisites

• Android Studio (latest stable)
• JDK 17
• Android SDK with API level 36

Build

# Clone the repository
git clone https://github.com/Musheer360/SwiftSlate.git
cd SwiftSlate

# Build debug APK
./gradlew assembleDebug

# Output: app/build/outputs/apk/debug/app-debug.apk

📦 Signed release build

export KEYSTORE_FILE=/path/to/your/keystore.jks
export KEYSTORE_PASSWORD=your_keystore_password
export KEY_ALIAS=your_key_alias
export KEY_PASSWORD=your_key_password

./gradlew assembleRelease

🤝 Contributing

Contributions are welcome! Here's how to get involved:

# 1. Fork the repository, then:
git clone https://github.com/YOUR_USERNAME/SwiftSlate.git
cd SwiftSlate

# 2. Create a feature branch
git checkout -b feature/amazing-feature

# 3. Make your changes and commit
git commit -m "Add amazing feature"

# 4. Push and open a Pull Request
git push origin feature/amazing-feature

Ideas for Contributions

• 🧩 New built-in commands
• 🤖 Additional AI provider integrations
• 🎨 UI improvements and new themes
• 🌍 Localization / translations
• 📖 Documentation improvements

📄 License

This project is licensed under the MIT License — see the LICENSE file for details.

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Made with ❤️ by Musheer Alam

If SwiftSlate makes your typing life easier, consider giving it a ⭐