Turn your phone into a precise spirit level, inclinometer & angle measurement tool
Available on Android & iOS
Bubble Level & Inclinometer is a free app by lapnito.cz s.r.o. that transforms your smartphone into an accurate digital spirit level and angle measurement tool. Using your device's built-in accelerometer and gyroscope sensors, it provides real-time measurements for leveling surfaces, measuring angles, and detecting slopes.
Available as Bubble Level & Inclinometer on Google Play and as Bubble Level & Angle Gauge on the App Store.
Whether you're hanging pictures, leveling furniture, checking wall alignment, or working on a construction site — this app replaces traditional bubble levels and inclinometers with a tool that's always in your pocket.
- Horizontal surface level — place your phone flat on any surface to check if it's perfectly level
- Vertical plumb level — hold your phone against a wall to check vertical alignment
- Bullseye level — two-axis leveling with a circular bubble indicator for precise surface leveling
- Visual and audio feedback when surface is level (within tolerance)
- Precise angle finder — measure angles from 0° to 360° with high accuracy
- Slope meter — measure slope and tilt in degrees or percentage
- Real-time digital display with large, easy-to-read numbers
- Hold/lock measurement — freeze the current reading for reference
- Built-in calibration — calibrate to your device for maximum accuracy
- Adjustable tolerance — set custom tolerance ranges (±0.1° to ±5°)
- Sensor fusion — combines accelerometer and gyroscope data for stable readings
- Accuracy comparable to physical spirit levels (±0.1° on modern devices)
- Clean, intuitive interface with large indicators
- Multiple measurement modes — switch between bubble level, inclinometer, and angle finder
- Multiple themes — light, dark, and high contrast styles
- Works offline — no internet connection required
- Lightweight — minimal battery and storage usage
| Use Case | How It Helps |
|---|---|
| Hanging pictures & shelves | Ensure perfect horizontal alignment |
| Leveling furniture | Check if tables, desks, and appliances are level |
| DIY & home improvement | Level surfaces during renovation projects |
| Construction & carpentry | Measure angles and slopes on job sites |
| RV & camper leveling | Level your vehicle at the campsite |
| Photography | Keep your camera perfectly level |
| Education | Demonstrate physics concepts (gravity, sensors) |
Modern smartphones contain a 3-axis accelerometer that detects the direction of gravity relative to the device. By measuring the gravitational force vector, the app calculates the exact tilt angle in all directions.
For enhanced accuracy, the app uses sensor fusion — combining accelerometer data with the gyroscope (which measures rotational velocity) to filter out noise and vibration, providing a stable and responsive measurement.
How accurate is a phone spirit level? On modern devices (2020+), the built-in sensors can achieve accuracy of ±0.1° to ±0.3° after proper calibration. This is comparable to many consumer-grade physical bubble levels.
Can I use my phone as an inclinometer? Yes! The same sensors that power the spirit level can measure angles with high precision. The app includes a dedicated inclinometer mode that displays angle, slope percentage, and pitch/roll values.
| Platform | App Name | Link |
|---|---|---|
| Android | Bubble Level & Inclinometer | Google Play |
| iOS | Bubble Level & Angle Gauge | App Store |
Website: lapnito.cz/bubble-level
Support: lapnito.cz/bubble_level_inclinometer/support.html
Q: Is Bubble Level & Inclinometer free? A: Yes, the app is free to download and use on both Android and iOS.
Q: Does it work without internet? A: Yes, the app works completely offline. No data connection is needed for any measurement.
Q: How do I calibrate the app? A: Place your phone on a known level surface, open the calibration screen, and tap "Calibrate." The app will adjust readings based on your device's specific sensor characteristics.
Q: Which devices are supported? A: Android 5.0 (Lollipop) and above, and iOS 13.0 and above.
Q: Is it as accurate as a real spirit level? A: After calibration, modern smartphones can achieve ±0.1° accuracy, which is comparable to consumer-grade physical levels. For professional construction requiring ±0.02° precision, a dedicated laser level is still recommended.
Q: Does it drain battery? A: The app uses minimal resources. Sensor readings consume very little power — significantly less than GPS or camera.
Q: What's the difference between the Android and iOS versions? A: Both versions offer the same core functionality. The Android version is called "Bubble Level & Inclinometer" and the iOS version is called "Bubble Level & Angle Gauge."
- Sensors: Accelerometer (TYPE_ACCELEROMETER) + Gyroscope (TYPE_GYROSCOPE)
- Sensor Fusion: Complementary filter for stable readings
- Android: Native Android, Min SDK API 21 (Android 5.0)
- iOS: Native iOS, Min iOS 13.0
- Languages: 17 languages supported
Built by lapnito.cz s.r.o. (Lapnito Development Studio), an indie development studio based in the Czech Republic.
- Website: lapnito.cz
- App page: lapnito.cz/bubble-level
- Support: lapnito.cz/bubble_level_inclinometer/support.html
- Email: tom@lapnito.cz
- More apps: Google Play | App Store
Made with ❤️ in Czech Republic by lapnito.cz s.r.o.