Bubble Level: Spirit & Ruler

Bubble Level is a precise spirit level, an on-screen ruler, an angle finder and a camera level in one small, fast app. The level reads your device's gravity sensor for smooth, jitter-free tilt, turns green the instant a surface is level, and shows the exact angle to a tenth of a degree. The ruler is calibrated to your screen, so a centimetre on glass is a centimetre in real life. No account, no sign-up, no tracking.

BUBBLE LEVEL / SPIRIT LEVEL
- Two-axis spirit level driven by the gravity sensor, smooth, no shake or jitter
- Surface mode, lay the phone flat for a bullseye that centres when level
- Edge mode, stand the phone on a side to level a shelf, frame, picture or wall
- Turns green the instant a surface is level, with a clear numeric readout
- Roll, pitch and slope shown at a glance

ANGLE FINDER / INCLINOMETER
- Measure any angle or slope, clinometer and protractor in one
- Read incline in degrees or percent grade for ramps, roofs, stairs and pipes

CALIBRATION
- One-tap calibrate against a known-level surface to zero out your device
- Reset returns to the factory zero. your calibration is remembered

SCREEN RULER
- On-screen ruler with centimetres down one edge and inches down the other
- Calibrated to your display's real DPI for true-to-size measurements
- Credit-card calibration fine-tunes the scale on any phone or tablet

CAMERA LEVEL
- Live level overlay on the camera preview for straight horizons and square photos
- The same green-when-level feedback over whatever you are framing

DESIGN & LANGUAGES
- Clean Material 3 interface with a true-black AMOLED dark theme, edge-to-edge
- Works in portrait and landscape, phone and tablet
- Available in 80+ languages

TYPICAL USES
Hanging pictures, shelves and mirrors. Levelling furniture, appliances and brackets. Checking a table, worktop or floor. Measuring small objects without a tape measure. Sizing a phone case or screen protector. Straightening frames on a wall. Levelling a tripod, TV mount or washing machine. DIY, woodworking, carpentry and quick repairs around the house.

PERMISSIONS
- Camera, used only for the optional camera level overlay (no photos or video are captured or stored)
- Internet, used only to load a single small banner advertisement

PRIVACY
No account. No sign-up. No subscription. No in-app purchases. No tracking and no analytics. A single small banner is served via AdMob, see the Data Safety section for AdMob's third-party disclosures. Made in Switzerland by an independent developer.

Get in touch: nils.roethlisberger@gmx.ch