PlumbLine: Level & Plumb

Are your walls, shelves and frames truly straight? Hold your phone to the surface — the whole screen turns green the instant it is. Plumb and level in one app.

Is that wall truly vertical? Is that shelf actually level? Hold your iPhone against the surface and PlumbLine tells you instantly — no bubble to squint at, no numbers to read. The whole screen turns green the moment it's straight.

HOLD IT, DON'T READ IT

• Press the back of your phone flat against a wall, post, door frame, shelf or picture frame
• A big target view shows the tilt front-to-back and left-to-right at a glance
• The screen flashes green with a beep and a tap the instant the surface is true — so you can adjust with your eyes on the wall, not the phone

VERTICAL AND HORIZONTAL, AUTOMATICALLY

• Put the phone upright against a wall and PlumbLine checks plumb (vertical)
• Lay it flat on a shelf and it checks level (horizontal)
• It senses how you're holding it and switches — you never pick a mode

MADE FOR STRAIGHTENING THINGS

• Hanging pictures and shelves, setting fence posts, aligning door frames, leveling furniture and appliances
• Set your tolerance: strict, standard or rough — the color verdict follows it
• Zero it against an existing surface to match a new one to it

SMALL TOUCHES THAT HELP

• Hold the reading to freeze it, then step back and check a spot you can't watch
• Save measured surfaces with a name to compare them later
• Choose degrees, percent slope or mm/m

PRIVATE AND SIMPLE

• One-time purchase. No subscription, no ads, no account
• Works fully offline. Nothing you measure ever leaves your device

PlumbLine is a planning aid. For precision construction, use a calibrated tool.