1. Install dependencies:

Navigate to the project repo directory.

Run:

npm install

assuming node installed in PC.

2. Run the development server:

Run:

npm run dev

This will run a server so game automatically opens in your defualt browser with browser-sync properties. It will also start a watch process, so you can change the source and the process will recompile and refresh the browser automatically.

Android vs iOS differences

1. In App Purchases (IAP): Android requires to have store.refresh() after store.order(). On the other hand, iOS will work only in the opposite order with the store.refresh() being placed before store.register(). It can be easily debugged what the server returns using JSON.stringify(store.products) on a real device with Android Studio/Xcode as per j3k0/cordova-plugin-purchase#1241 (comment).
2. "x" button in main menu: iOS should not have it, whereas Android should have.