Cannot find name CKEDITOR Ionic 4

Hi,i am working on an Ionic project. I am trying to integrate CKEditor library. I am getting some problems though. My code is as follows:

import ‘ckeditor/ckeditor’;

var textarea = document.getElementById(‘editor1’);

CKEDITOR.replace(document.getElementById( ‘editor1’ ), {
toolbarGroups: [{
“name”: “basicstyles”,
“groups”: [“basicstyles”]
removeButtons: ‘Underline,Strike,Subscript,Superscript,Anchor,Styles,Specialchar’

When i try this: declare var CKEDITOR: any;
it is working on the browser ,but not on the iPad. On the device it is not visible at all.
I was wondering ,if you could help me ,please?
Thank you in advance.