Are you using any plugins? Vibration or something that isn’t supported in GNOMEs WebKit browser?
Cordova is just a browser/webview with an app around it, Java for android and Objective-c for iOS so you cant run those directly. I guess you could use Electron or wait/hope they will add support for PureOS.
I’ve made several apps using Cordova, but seldom used anything that isn’t supported in a browser anyway. Those apps will run as web-apps.
I tried my apps in GNOMEs “Web” to test them and see that everything worked.
I’m just a webdeveloper my self so I could be wrong 