Question: I am creating an API with our API server script and am trying to communicate with the API on the IONIC framework application. I am working but it keeps on bringing up the cross-origin blocked error: 

[![enter image description here](https://i.stack.imgur.com/x1jg4.png)](https://i.stack.imgur.com/x1jg4.png)

Answer: 
If you have no way to change the server configuration, you should use [Http native plugin](https://ionicframework.com/docs/native/http/) to perform Http requests from your mobile device, to prevent cors problems. However, in web enviroment you still need to use Angular's HtttClient. Fortunately, with [ionic-native-http-connection-backend](https://github.com/sneas/ionic-native-http-connection-backend) library you can use the same HttpClient service for both enviroments, and Http native will be used internally if the app is executed from a mobile device. It's a kind of wrapper.
The issue is just during development phase ,the best way to deal with it is to install "Allow-Control-Allow-Origin" extension in chrome.