Bubble Level

Turn your phone into a precise, pocket-sized bubble level.

Bubble Level uses your device's built-in accelerometer to measure surface tilt in real time. Everything runs on-device — no internet, no ads, no tracking, and no runtime permissions required.

KEY FEATURES

• Circular bubble view — one glance tells you if a surface is level in both directions.
• Two horizontal tube views — clear left/right (roll) and front/back (pitch) readings.
• Live degree readouts — pitch, roll, and combined tilt shown to 0.1°.
• "Level" indicator — the bubble turns green and the center ring highlights when you are within 1°.
• One-tap calibration — place your phone on a known-flat surface, tap "Calibrate to Level", and the current position becomes your zero reference. Tap "Reset" any time to restore the factory zero.
• Dark and light themes — follows your system setting.
• Fully offline — no network access, no analytics, no advertising SDKs.
• Tiny app size and instant startup.

TYPICAL USES

• Hanging pictures, shelves, and TVs straight.
• Leveling furniture, appliances, and camera tripods.
• Checking floor, table, and countertop flatness.
• DIY and woodworking projects.

PRIVACY

Bubble Level does not collect, store, or transmit any personal information. It does not ask for any Android runtime permission. The accelerometer reading is used only to draw the on-screen bubble and never leaves your device. A small local file remembers your calibration offsets; you can clear it in-app or from system settings at any time.

Full privacy policy: see the Privacy Policy link inside the app or on our store listing.

TIPS FOR ACCURATE READINGS

• Calibrate against a surface you know is truly level (a spirit level or machined flat plate works well).
• Sensor accuracy varies slightly by device. If readings look off after calibration, tap Reset and calibrate again on a better reference surface.
• Keep the phone case flat against the surface, without dust or crumbs underneath.