Percivo is a mobile accessibility utility that helps users read and inspect small text or UI elements on their Android screens. It provides a floating magnification lens that enlarges any portion of the screen in real time — working on top of any application, without requiring the app to natively support zoom.
Percivo is built for clarity. Whether you're reading dense fine print, inspecting a complex UI, or navigating an interface that was not designed with visual accessibility in mind, Percivo gives you instant, precise magnification — exactly where you need it.
Percivo — from Latin, meaning "to perceive clearly."
- Floating Magnification Lens — a resizable, draggable lens overlays any screen content in real time
- Full-Screen Magnification — magnify the entire display for maximum readability
- Hybrid Mode — seamlessly switch between lens and full-screen magnification
- Adjustable Zoom — pinch to zoom or use the slider; supports fine-grained zoom control
- Multiple Lens Sizes — choose from small, medium, large, or full-width lens profiles
- Always-On Mode — keep magnification active as you move between apps
| Method | Description |
|---|---|
| Floating Button | Persistent on-screen accessibility shortcut |
| Triple-Tap Gesture | Tap the screen three times to toggle the lens |
| Volume Shortcut | Hold both volume buttons simultaneously |
- Drag handle for repositioning the lens
- Pinch gesture to adjust zoom level
- Zoom level slider for precise control
- Smooth scrolling support
- Press-and-hold for temporary magnification
- Activate — trigger Percivo using any of the supported shortcuts (floating button, triple-tap, or volume hold)
- Lens Appears — a floating magnification lens overlays your current screen
- Move & Zoom — drag the lens to the content you want to inspect; pinch or use the slider to adjust zoom
- Dismiss — swipe the lens away or tap the shortcut again to close
Percivo uses Android's Accessibility Service API to render a real-time magnified view of the screen, making it compatible with virtually any application.
- Android 8.0 (API level 26) or higher
- Accessibility Service permission
Play Store listing will be available upon public release.
- Download the latest APK from the Releases page
- On your device, enable Install from Unknown Sources in Settings → Security
- Open the downloaded APK and follow the installation prompts
- Grant the required permissions when prompted
# Clone the repository
git clone https://github.com/MohdAqdasAsim/Percivo.git
# Navigate to the project directory
cd Percivo
# Open in Android Studio, or build via CLI:
eas build --platform android- Open Percivo
- Tap Enable Accessibility Service and grant permission in Android Settings
- Return to Percivo and configure your preferred activation method
- Tap Start to activate the lens
- Pinch gesture on the lens to zoom in or out
- Use the zoom slider in the control panel for precise adjustments
- Double-tap the lens to reset zoom to default
Navigate to Settings → Lens Size and choose:
- Small
- Medium
- Large
- Full Width
Enable Settings → Always-On Mode to keep Percivo active across app switches. Zoom resets when switching apps, but the lens remains ready.
| Permission | Purpose |
|---|---|
ACCESSIBILITY_SERVICE |
Required to render the magnification overlay over other apps |
SYSTEM_ALERT_WINDOW |
Allows the floating lens to appear above other applications |
FOREGROUND_SERVICE |
Keeps the magnification service running while in use |
Percivo does not collect, store, or transmit any screen content or personal data. All processing is performed locally on-device.
Percivo was built first and foremost as an accessibility tool.
It is designed to serve:
- Users with low vision or visual impairments who benefit from on-demand magnification
- Users who need to read small text in apps that do not support native zoom
- Users in environments where adjusting display settings is inconvenient
- Developers and designers inspecting UI details at a fine level
Percivo complements Android's built-in Magnification feature by offering greater flexibility, faster activation, and a non-intrusive lens overlay that does not disrupt the underlying interface.
Percivo/
├── app/
├── docs/ # Additional documentation
├── assets/ # Logos, screenshots, media
├── wbsite/
├── README.md
├── CONTRIBUTING.md
├── CODE_OF_CONDUCT.md
├── CHANGELOG.md
├── metadata.yaml
└── LICENSE
Contributions are welcome and appreciated. Please read CONTRIBUTING.md for guidelines on how to get started, submit issues, and open pull requests.
This project follows a Code of Conduct. By participating, you are expected to uphold these standards in all project spaces.
This project is licensed under the MIT License. See the LICENSE file for details.
Built to make every screen readable for everyone.