Waterpass - Bubble Level

Waterpass turns your phone into a precise digital spirit level — a familiar tool, redrawn on screen, so you can check level and plumb without carrying a physical level around. Two measuring modes cover the situations a real spirit level is built for: lay the phone flat for a two-axis bullseye reading, or stand it on its edge for a classic three-vial bar, exactly like a traditional aluminium level. The sensor reading is always the source of truth — the on-screen bubble is simply the clearest way to see it. WHY WATERPASS • Bar mode (landscape) — three vials in one view: vertical, horizontal, and 45° diagonal, just like a physical level held on its edge. • Round mode (portrait) — a bullseye bubble reads both tilt axes (X/Y) at once, for laying out tabletops, appliances, and tripods. • Precision calibration — correct your own phone's sensor offset once per edge, so readings stay accurate on the exact device you own. • Calibration quality at a glance — a simple light shows exactly how good each edge's calibration is, so you know when to trust a reading. • Three units — switch between degrees, percent, and mm per metre to match how you already measure on site. • Sound & vibration confirmation — get an unmistakable cue the instant a surface reads level, without staring at the screen. • Hold & Copy — freeze a reading to note it down, or reference a saved angle while you adjust. • Alt 0° reference — zero the display against any reference angle, not just true horizontal. • Guided tutorial — a short, one-time walkthrough explains every button, light, and readout the first time you open each mode. • No sign-up, no cloud — calibration profiles and settings stay on your phone, not an account. WHO IT'S FOR Whether you're framing a wall, installing cabinets, assembling furniture, or just hanging a picture straight, Waterpass is built to support you — on the job site or around the house. A NOTE ON SUPPORT Waterpass is free to use, supported by ads, which need an internet connection to load. It doesn't request more device permissions than it needs, and it doesn't collect the measurements you take. Accurate, uncluttered, and ready whenever you need to check level.