Hi Glen,
Greetings from Syncfusion support.
We have checked the reported issue in iPad device. Your reported problem not occurred in our validation in IPAD device.
By default, openOn is set to auto. Based on the device mode, open behavior of tooltip will be determined. In desktop mode, it will show the Tooltip content when hovering on the target element.
In touch device, it will show the Tooltip content when tap and holding on the target element. If you set openOn as hover, then tooltip will be open when touching the target element of Tooltip.
Please, let us know if you need any further assistance.
Regards,
Shameer Ali Baig S.