Thank you for providing detailed information about your observations and scenario. Indeed in iOS the items have fixed size of 44 and currently the items does not respect the size set by the ItemTemplate. We confirm this is a bug in the RadTreeView component. I logged it in our feedback portal
At the time of writing we are not aware of a suitable workaround. Even though we cannot bind to any specific time frame for fixing this issue we will try to fix it in some of the future releases.
As a small sign of appreciation of your feedback I updated your Telerik account accordingly. I hope this issue is not show stopper for you and you will be able to continue the development.
Pavel R. Pavlov
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