TrueLevel · for iPhone
A spirit level that also tells you the angle
Lay the iPhone on a shelf, a frame or a worktop and read it two ways at once: a bubble that drifts to the high side, and pitch and roll in degrees to one decimal place — big enough to read from across the room.
How it works
- Lay it on the surfaceThe bullseye bubble drifts toward the high side and turns green the moment you are within tolerance.
- Read both axes at oncePitch and roll get their own vial and their own number, to a tenth of a degree.
- Zero it on anythingCalibrate against any reference surface and measure every tilt relative to it — handy when the phone's own back is not flat.
- Keep the angle (Pro)Capture a reading, label it — "Top shelf" — and keep a history of them.
What it looks like
Pitch, roll and what a degree means
Pitch is the tilt along the phone's length — top edge up or down. Roll is the tilt across it — one side up or down. A spirit level shows you one of them at a time; TrueLevel shows both, so you can level a surface in one go instead of turning the tool round.
A degree sounds small. Here is what the tolerance settings mean over a metre, and over the length of a 4-foot level:
| Tolerance | Rise per metre | Rise over 4 ft |
|---|---|---|
| 0.2° | 3.5 mm | 0.17 in |
| 0.5° | 8.7 mm | 0.42 in |
| 1.0° | 17.5 mm | 0.84 in |
| 2.0° | 34.9 mm | 1.68 in |
Pick the tolerance to suit the job: 0.2° for a shelf you will look along, 1–2° for a washing machine that only has to stop walking.
How to check if something is level with your iPhone
- Mind the camera bumpA bare iPhone rocks on its camera bump when it lies on its back. Zero it the way you will use it — same case, same side down — on a surface you trust, and every reading after that is relative to it.
- Bridge long surfacesThe phone only reads the few inches it sits on. For a long shelf or a worktop, lay a straight edge across and put the phone on that.
- Check both directionsA surface can be level one way and not the other. With pitch and roll on screen at once, you see both without turning the phone.
Free, with a one-time Pro
The level, both readouts, zeroing and the tolerance setting are free. TrueLevel Pro is a one-time purchase — no subscription — that keeps captured readings in an angle log.
Honest about the limits
- A phone, not a surveyor's instrument. It is right for shelves, frames, appliances and tripods. For foundations or framing to code, use a proper level or a laser.
- Only as flat as what it sits on. A case, a lip or a crumb under the phone changes the reading — zero it on a known surface first.
- No account. Readings stay on your iPhone.
Last reviewed 22 September 2026