Navigation pages is too slow and sometimes without content

Product: Webviewer

Product Version:
Webviewer 8.6.1 (javacript)

Navigation between pdf pages is too slow and sometimes without any content. We have this problems for linearized pdf too.
Also we download pdf documents completely on the device.
Navigation pages has a good performance in the browser, but not in mobile (ios) app.
Our application are developed with ionic, cordova and angular.
Firstly, we tried to implement webviewer in our app with cordova but didn’t work, so we used javascript to implement webviewer. We know javascript’s engine in mobile’s browser is slow.

We are wondering if you could test out this demo page on your mobile devices? We have some performance improvements in version 8.7 and our demo page is currently running 8.8. Overall we are having a smooth experience when viewing documents on a base iPhoneX.
Thank you and please let us know your experience there.