Desktop Ruler brings two measuring tools to your laptop screen or monitor. The main measuring tool is (obviously) a ruler but the utility also features a so-called “Precise Measuring Tool”. With it, you can measure the exact distance between two points (pixels), the angle of the straight line that connects them and some other data. The tool is really precise because it allows you to easily pick the exact pixels you need with the help of a magnifier that can zoom in up to 15X.
Because the program has no main window, settings are adjusted by right clicking on the ruler that is displayed on the screen. This may annoy some users, as it feels rather unnatural to navigate through such a long vertical menu with so many elements. Fortunately, some features have hotkeys assigned to them. Unfortunately, some actions that may be needed often, aren't associated with shortcut keys. For example, some users may need to change the measurement unit on the ruler (between pixels, inches, or centimeters). Having to go through two submenus each time you want to do this is definitely not a pleasure.
Both measuring tools can be customized to the detail.
It's normal for a trial version to be limited in some ways but it's a mistake to deny access to an essential setting: you cannot manually adjust the DPI (dots per inch) value. Because of this, if none of the presets matches the DPI of your display, the measuring units displayed on the ruler will not be accurate.
This is, at its core, a good program but the few slip-ups lower its quality, making it just a so-so product.