Cordova 'device' plugin, I keep getting ReferenceError?

Uncaught ReferenceError: device is not defined

Above is the Error I receive when using this: device.model

I have installed the plugin correctly, I have cordova.js in my HTML file...

I Basically want to use this code after the device is ready...

model = device.model;
alert(model); // shows: iPhone7,1 or whatever
if (model === iPhone7,1) {
    var imgData=ctx.getImageData(0,0,3*x,3*365*Yf);
} else {
    var imgData=ctx.getImageData(0,0,2*x,2*365*Yf);
}

FULL CODE: https://github.com/GunZi200/Memory-Colour/blob/master/test.js

HTML: https://github.com/GunZi200/Memory-Colour/blob/c1b95d60510302a5367ae2ae6137c2d840d99c60/index.html