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Ruler | A Curious Tool

By Curious Hat

This app is only available on the App Store for iOS devices.


Measure and compare objects around you!

With Ruler, users can explore and measure objects around them and learn about sizes, units of measure, and proportions.

* Simply pick a known reference object in Ruler, like a coin or a sheet of paper, then select an object you’d like to measure.
* Place these objects side-by-side and take a picture.
* Ruler provides sliders to measure the objects and compares their relative sizes.
* Switch between the US and Metric measurement system.

36 Reference objects to choose from including:
- US and World coins and paper bills
- iPhone and iPad
- Credit Card
- Crayon
- Lego and Duplo bricks
- US and A4 paper sheets
- soccer, tennis, basket, baseball, golf, football balls
- soda can

Note for parents and educators:
The app shows iAds.
If you want an ad free version of this app, please download Curious Ruler


iPhone Screenshot 1
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iPad Screenshot 1
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Customer Reviews

Actually works!

Very neat concept, very helpful. 👍


Works great👌✨

Ruler | A Curious Tool
View in iTunes
This app is designed for both iPhone and iPad
  • Free
  • Category: Utilities
  • Released:
  • Version: 1.0
  • Size: 7.4 MB
  • Languages: English, French, Italian
  • Seller:

Compatibility: Requires iOS 6.0 or later. Compatible with iPhone, iPad, and iPod touch.

Customer Ratings

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