Vulcan’s Level
Vulcan, Roman god of the forge, the only god who worked, was known for the beautiful things he crafted in his foundry. Vulcan used only the best tools. This carpenters level is the level that Vulcan would have used. If he existed. And if he had a smart phone.

Okay, maybe a Roman god wouldn’t have used a level app on a smart phone. Maybe he could just put his hands on a surface and feel even the smallest tilt. I mean, he was a god, right? So what makes this level app so useful that it bears the name of a Roman god?

It uses a unique calibration process that doesn’t require a level surface.

Yeah, there are a lot of carpenter’s level apps out there. And while most smart phones have a gravity sensor, most of them aren’t installed with precision, so most of these apps aren’t very accurate unless you can calibrate them. A lot of smart-phone levels have a “Calibrate” button, but you first need to put your device on a surface that you already know is level. And to know that, you need a carpenter's level that’s already calibrated!

So how useful is that? Well, not very. So your level’s calibration button probably doesn’t do you much good.

Here’s where Vulcan’s Level  beats all the other smart-phone levels: It uses a unique two-stage calibration process. By measuring a surface from two different orientations, it can compensate for a tilted surface. So it can give you a true calibration, even from a surface that’s not truly level. Kind of like putting your hands on a surface and just feeling even the smallest tilt. How does that work? Well, download the app and try it yourself.

IN THE APP STORE
IN THE PLAY STORE
  1. Unique Calibration Process
    Most mobile-device levels require a level surface to calibrate. Level of Vulcan may be calibrated on any firm surface. The two-stage calibration process measures the tilt of the surface two ways, two errors to cancel each other out, giving you a correct calibration anywhere.
SCREENSHOTS
Optional axis lines show when your central bubble is on one of the two axes. When both lines show, you're level, within your selected accuracy.
Turn your mobile device on its side and you'll see a wide view or a high view.
Pick whatever fluid color suits your fancy.
You can set the degree of accuracy that determines how close to true level you want to detect. An inexpensive carpenter's level might have an accuracy of 2:1000, or two parts per 1000. A more expensive level might have an accuracy of 1:1000 or even 1:2000. Vulcan’s level lets you choose the accuracy needed to indicate when your surface is level. 

Of course, this setting doesn't affect the accuracy of the internal sensor. And some smart phones will have better sensors than others. Vulcan's Level, and any other smart-phone level, can't make any promises about the accuracy of your smart-phone's sensor.
You may display the measured angles in degrees, in percent (rise/run), or in American roofer's units, which show inches of rise per foot of run.