The software's interface has some issues regarding the visibility of main menu thumbnails. Other than that, the interface could've been more consistent and could've had better starting templates.
In order to start using PhoneGap, all you need to do is select a folder location for your project and name it. The project will then be loaded in the main screen along with a server address at the bottom of the window.
The program offers access to native device APIs, such as camera, GPS, accelerometer, so that the application that it's being built acts just like a native app.
The main attribute of the program is that you can use the same code on multiple platforms, like iPhone, Android or Windows, without being needed to write the code from scratch for every platform.
In conclusion, I'd say PhoneGap Desktop is a strong alternative to Ionic, and despite some GUI issues, is a useful solution for deploying applications faster and smoother.