Bubble Level: Spirit Level

Bubble Level is a bubble level tool and spirit level app for your phone, so you can check tilt and level shelves, frames and furniture without hunting for a toolbox. You find out the shelf was crooked after the screws are in. Eyeballing it looked fine, the picture frame "seemed straight", and the real spirit level is in the garage, in a toolbox, under something, never in the room where the work is happening. So things get hung slightly wrong, and every glance at that tilted frame reminds you.

This bubble level app is the level that is always in your pocket. Lay the phone on the shelf, hold it against the frame, and the bubble tells you immediately, drifting while the surface is off, turning green the moment it's level, with the exact tilt in degrees on both axes if you want the number.

KEY FEATURES
• Real-time bubble: a smooth, responsive indicator driven by the phone's accelerometer
• X/Y tilt readout: the precise angle in degrees on both axes, to one decimal
• Green at level: an unmistakable visual signal the second the surface is true
• Vibration feedback: an optional haptic pulse at level, so you can watch the screws, not the screen
• One-tap calibration: zero against any reference surface (a countertop, a known-level shelf) in seconds
• Flat or on its edge: works lying flat on a surface or standing on an edge against a shelf or frame
• No setup: no account and no configuration; open it and place it

MADE FOR
• Hanging pictures, mirrors, shelves, and curtain rails straight the first time
• Checking washing machines, fridges, and furniture that wobble or drift
• Leveling a camera tripod, record player, or workbench
• Tradespeople who need a fast sanity check on-site with a phone spirit level instead of walking back to the van
• Campers and caravanners leveling a van, trailer, or stove

Calibrate once against a known surface, and every check after that with this spirit level is just: place the phone, watch for green.

Recent changes:
- Fixed: after you zero the level, the History button no longer slides off the screen in German, French and other long languages, or at large text sizes.
- Clear all in History now asks before deleting your saved readings.
- Save reading stays off until the sensor is actually reading, so no fake 0.0 entries.
- Screen readers announce when the surface becomes level or stops being level, instead of reading every number.