All it takes to start tracing is to drop an image into the app, you do not have to sign up or go through a complicated setup process.
The app is built with web technologies, which means it can be used inside a web browser without having to go through the hassle of installation wizards or figuring out if the app is compatible with your operating system.
When used for the first time, it is automatically installed and can be used without an Internet connection afterwards.
Choose any of the included analyses and the app steps you through it so you can finish tracing in a few seconds.
Measurements are calculated immediately as you are tracing.
... read the whole story at github.com.