Steps to follow for running your app on browser, device or deploy as PWA
Run the app on Browser
Once you have the initial setup done, it's time to run your app. First we'll run the app in development environment. In development environment, your app runs in a browser (of your choice). It is recommended to make all changes and development while running the app on browser . Running on device while developing will be too time consuming.
To run the app on browser, run
$ ionic serve
on your command line, inside your project folder. This will build the project and deploy it on a localhost url (usually it is localhost:8100). Your command line will look like this
The initial deploy process will take some time when it creates "chunks" of code pieces. Once you see compiled successfully , you are good to go. Your browser window will open automatically and load the app in a full screen view.
Sometimes, the CLI does not open the browser automatically. In such case, open your browser and type URL localhost:8100 to start the app.
To change the app to a device view, right click anywhere on the browser and choose Inspect Elementand choose device mode. The app will look like this in device mode
More about browser development tools can be found out in following links