TrueBubble
Dual-axis level, bullseye mode, and real calibration - so readings you can actually build with.
Two vials, one screen - pitch and roll measured and shown at the same time, in degrees.
Level a flat surface in both directions at once - tripods, appliances, tabletops.
Horizontal and vertical vials on screen together, with numeric readouts for each axis.
A circular bubble level for flat-surface leveling in every direction.
Bubbles and numbers shift color as you approach level - correct at a glance.
One-tap auto calibration against a known-flat reference, or fine-tune offsets by hand.
Lock a reading in place for reference while you reposition the device.
An optional signal the instant you hit zero - for hands-busy, eyes-elsewhere work.
Plus a high-contrast bubble mode for bright-light readability.
No internet access requested, no account, no data collection.
Place your phone on a known-flat reference and one tap zeroes the sensor offset, with step-by-step on-screen guidance. No guesswork, no drift left uncorrected.
Want more control? Manual calibration lets you fine-tune pitch and roll offsets directly with +/- controls, and always shows exactly when the device was last calibrated.
Switch between dark and light themes, or flip on high-contrast bubble mode for better visibility outdoors.
Pick from 9 bubble colors to match your eye, your job site, or just your taste.
TrueBubble runs entirely on-device, using only your phone's motion sensors - confirmed in the app's own privacy policy.
Free on Google Play. Precision leveling, fully offline.