Protractor: Angle & Level

appcellent

In-app purchases

About this app

Turn your phone into a precision angle measuring tool. Protractor measures angles using your device's motion sensors or camera — no extra hardware needed.

Whether you're checking a roof pitch, setting up a workout, hanging a shelf, or finishing a geometry assignment, you get a fast and accurate reading in degrees, percent slope, or roof pitch notation.


▸ THREE WAYS TO MEASURE

• Sensor mode — rest your phone on any surface and read the angle directly from the built-in motion sensors.
• Camera mode — point your camera at an object and measure the angle on screen without touching it.
• Photo mode — import a photo from your gallery and measure angles on the image.


▸ BUILT-IN BUBBLE LEVEL

A full spirit level is included. Use it as a digital level, bubble level, or level tool to check whether a surface is flat, plumb, or square.


▸ 18 MEASUREMENT MODES

Each mode is tuned for a specific job, with the right units and guidance:

• Body & Joint Angle — knee, elbow and hip range of motion, like a digital goniometer
• Surface & Corner — angle between two walls or surfaces
• Terrain & Slope — ground slope, driveway and grade %
• Hang & Level — level frames, shelves and furniture
• Workout Form — squat, bench and exercise form angles
• Geometry & Homework — measure angles on shapes and paper
• Knife Sharpening — bevel and edge sharpening angle
• Sports & Hobby — climbing, 3D printing, archery
• Automotive — camber, seat recline and driveshaft
• Bike Fit — knee, back and saddle angles
• Plumbing & Pipe — pipe bends and conduit angles
• Audio & Speaker — speaker toe-in, monitor and TV tilt
• Stairs — stair pitch and handrail angle
• Measure on Photo — import a photo and measure on it
• Astronomy & Dish — azimuth and elevation for dish or scope
• Roof Pitch — roof pitch in degrees and x:12
• Golf Club — club lie and loft angle
• Solar Panel — panel tilt and best sun angle


▸ MADE FOR REAL WORK

• Switch between measurement units to match the job
• Sound and haptic feedback so you know the moment you hit the target angle
• Clean, readable display that works at arm's length
• Works offline — no internet connection required


▸ WHO IT'S FOR

Carpenters, woodworkers, roofers, DIYers, mechanics, plumbers, electricians, physiotherapists, coaches, students, photographers and anyone who needs an angle finder in their pocket.

Use it as a protractor, angle finder, angle meter, inclinometer, clinometer, slope meter, tilt meter, goniometer, degree finder, spirit level or digital level — all in one app.


▸ ACCURACY NOTE

Readings depend on your device's sensors and how the phone is held. Protractor is built for practical, everyday measurement — for work requiring certified tolerances, confirm with a calibrated instrument.


▸ SUBSCRIPTION

Protractor is free to download and includes core angle measurement. A subscription unlocks all measurement modes, unit switching, and sound and haptic feedback.

• Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period.
• Manage or cancel your subscription in Google Play Store settings.
• A free trial, where offered, converts to a paid subscription unless cancelled before it ends.

Terms of Use: https://protractor.appcellent.co/terms
Privacy Policy: https://protractor.appcellent.co/privacy

Questions or feedback? https://protractor.featurebase.app

What’s new

• Measure angles with sensors, camera or an imported photo
• Built-in bubble level
• 18 measurement modes
• Sound and haptic feedback