This app was built to work with the TrainEasy web app API. You will need to purchase and install a copy of TrainEasy before you can use this app. You can buy it here: https://codecanyon.net/item/traineasy-training-management-registration-system/19457888 .
Once your TrainEasy web app is installed and working, you will need to update the api in your Ionic app to work with your installed application. To do so, please open the file located at src/app/config.ts . You should see code as below:

export const CONFIG = {
   apiUrl:'https://demov1.traineasy.net/api/v1'
}

You need to change text https://demov1.traineasy.net to point to your server. Ensure you do not remove the quotes (') or the api string (/api/v1) . Also ensure there are no spaces after you change the code