Open your terminal and navigate to the project folder ( API version directory or Firebase version directory ) and install NodeJS dependencies:
** $ npm install **
Once node dependencies are installed successfully you can run the app in browser window with:
** $ ionic serve**
If you get any any error while running this delete the nodule modules and try still if the errors exists try executing this is another port for ex: https://localhost4600 by running the command called ionic serve --port 4600
You can also run this app with Ionic Lab, It will open apps in multiple device at a time and it's good way to Test your own apps.
**$ionic serve --lab**
If there is any issue please google it or if you fail to find any solution please feel free to report us, we will look into it.