Turn your iPhone into an aerospace-grade precision instrument. Check surfaces, verify plumb walls, calibrate once, and save measurements β all in a calm, beautifully crafted interface.
When you find true level, the interface shifts to a calm, luminous green β the zen moment of perfect alignment.

Every pixel is crafted with the quiet beauty of a machinist's tool

Landscape horizontal vial for shelves and edges






Everything a precision level needs, nothing more
Lay your iPhone flat on a surface to measure inclination. Two-axis bubble instrument with smooth rolling-digit readouts.
Press the back of your phone against a wall to check if it's truly vertical. Includes a hold-posture indicator.
Zero out sensor drift on a known-flat reference. Calibration offsets persist across launches β do it once.
Lock any measurement into an elegant log, grouped by day, with editable notes and swipe-to-delete.
Quiet, precise, and private by design
Rotate your iPhone to use a long horizontal bubble vial, optimized for picture frames, shelves, and countertops along their length.
Gentle Taptic feedback when you reach perfect level, save a measurement, change tabs, or calibrate successfully.
Measurements accurate to one tenth of a degree, with smooth digit transitions that feel like a laboratory instrument.
Automatically detects when iOS rotation lock prevents the interface from rotating, and guides you to unlock it.
No accounts, no cloud sync, no analytics, no network requests. Every measurement stays on your device.
Beautiful light and dark app icons that automatically match your iOS appearance setting.
Point. Press. Save. It's that simple.
Place your phone on a surface you trust to be flat, wait for the stability meter to fill, then tap ZERO OUT.
SURFACE for horizontal things, PLUMB for vertical things. The reading is live and smoothly animated.
Tap LOCK MEASUREMENT to save the reading with a timestamp and optional note. Review anytime in HISTORY.
Download ZenLevel and turn your iPhone into the precision level you'll actually enjoy using.
Download from App Store