Simple Ruler

Simple Ruler turns your phone screen into a pocket-sized measuring stick you can trust for quick, everyday measurements. Lay a small object directly on the display, read the value off the on-screen scale, and move on. No calibration cards required to start, no sign-in wall, no clutter.

What you can do:

- Measure in metric with major ticks at every centimetre and minor ticks at every millimetre.
- Switch to imperial with a single tap and read inches down to 1/16 of an inch.
- Fine-tune the scale with the built-in DPI calibration when a millimetre needs to be a real millimetre. Enter a reference length you know, such as the width of a credit card or a coin, and Simple Ruler remembers your calibration for every launch after that.
- Start measuring the moment the app opens. There is no home menu, no wizard, no promo screens.

Why choose Simple Ruler:

- Fully offline. The app never opens a network socket.
- Zero permissions. The manifest declares no runtime permissions, no INTERNET, no location, no storage, no camera, no microphone.
- No ads and no advertising SDK.
- No in-app purchases and no billing SDK.
- No analytics, no tracking, no crash reporting SDK.
- Small install size and quick startup on modest hardware.
- Clean Material Design surface with automatic day and night themes that follow your system setting.

Simple Ruler is designed for makers, hobbyists, students, seamstresses, and anyone who occasionally needs to check a dimension without unpacking a tape measure. Compatible with Android 7.0 (API 24) and newer.