The Kendo Chart is a tool that's used mostly for visualization purposes, and not for editing. However, we have some great widgets which can edit such as the Kendo Grid.
One possible suggestion, consider using a shared Kendo Datasource
with an editor like the Kendo Grid
and a Chart. With the Kendo Grid, you can edit the category names and the values. Then, you can show the results in a Chart. Here is a Telerik Dojo illustrating the approach.
Pertaining to the Tooltip, there is no direct way to keep it open at all times.
I hope this clears things.
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