Have a ruler or grid on your screen any time, any where, with the push of hotkeys. The ruler can automatically measure objects shown on the screen - virtually any objects. Works great with other apps. This is a must-have tool for graphic design or picture editing.

Premium features include:
- Easy switching between units (pixel, inch, cm)
- Provides pixel-level detail for measurement
- Allows for free vertical or horizontal movement of ruler on screen
- The smart ruler automatically recognizes objects which user intends to measure and provides dimensional data immediately
- A grid (adjustable) can be turned on to assist positioning in your own applications
- The ruler/grid will not interfere with other apps running at the same time. instead, “Ruler on Call” allows you to measure objects and help position them in any other apps, especially when they don’t have a built-in mechanism for object alignment or resizing guidance.
- Currently does not support full-screen mode

“Ruler on Call” lets you lay a grid or use a ruler over other app’s screen and even automatically measures objects for you to help you stay productive. You will definitely love its utility and ease of use.

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What’s New

Version 16.4.10

* Code modernization
* Fixed an issue where the position of control panel when launched may not be correct for some users


Stony Labs, LLC
6.5 MB
OS X 10.7 or later
Age Rating
Rated 4+


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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