The Android issue is fixed. The issue on iPhone with iOS 12 will not be fixed. The issue is not reproducible with iOS 13+ on iPhone, as mentioned in issue's description. If iOS Safari alerts "Popup blocked" on trying to print, make sure to enable popups from Safari browser settings.
Thank you for this feedback. I am reproducing the issue on my side on iOS 12.4.4 iPhone device with Safari browser and on an Android 10 with Chrome 79 browser. Currently there is no known workaround for it.
I am converting this support thread to a publicly visible issue in Kendo UI Ideas and Feedback Portal. As a small token of gratitude for reporting this issue, I am updating your Telerik points.