The lack of a horizontal scrollbar is noticeable :))

ComboBox initialization
  $(document).ready(function(){
      $("#combobox").kendComboBox();
  });

is missing an o in kendo

It would be nice in the grid or treeview modules to have a "DblClick" event handler. 

Allows to bind, fire and assert key combination strings against all these Kendo UI widgets and events. Such as using keyboard shortcut to handle grid row selection or using keyboard shortcut to go to next page ... etc.

Allow charts to define multiple chart areas.  

This would be particularly useful in scenarios where historical data for an industrial process must be visualized in line charts (e.g. temperatures, pressures, valve positions, flow rates etc.)

CKEditor provides the "Insert Template" feature which gives the user the ability to design/create HTML Templates, add it to the toolbar menu, and reuse them. Please see the CKEditor documentation below for reference:

1. http://ckeditor.com/about/features#user-rich-content (see "Templates" on the right)

2. http://docs.ckeditor.com/#!/api/CKEDITOR.template

3. http://ckeditor.com/addon/templates

This will be a tremendous addition to the Editor, giving us the ability to create special-purpose HTML snippets, add them to the toolbar, and reuse them throughout (e.g., footnotes, bibliographic entries, etc).

When grid use popup edit, click cancel or close, the top row removed.

Add support for multiple axis for charting.

Currently the Kendo AutoComplete can show more than one piece of data in the drop down when you define the template accordingly. The downside is that you can't have header to describe each piece of information.

Listview scrolling becomes very laggy after more than 30 or so items are bound via endless scrolling or pull-to-refresh. In the article below by Chris Love he discusses Facebook's decision to abandon html5 for native apps and states the fault isn't necessarily with html5. He suggests techniques such as removing DOM elements when the markup is scrolled far out of view and not reachable with 2-3 flicks that could drastically improve performance for scenarios such as the Facebook infinite scroller. Would it be possible to implement a performance-enhancing technique such as this as a built-in feature of the KendoMobileListView scrolling? I have already made it a practice to never use With Blocks in my ListView item templates by assigning { useWithBlock: false } and would appreciate any other performance optimization options.

http://professionalaspnet.com/archive/2012/12/27/Don_2700_t-Make-Facebook_2700_s-Mistake_2C00_-Architect-for-the-Modern-World.aspx

To support various language,
I think KendoUI need language pack system.

Current globalization supports only currency, number format and few label for calendar.

It's so hard to change default english label for buttons and messages.
Sometimes, It's hardcoded in kendo.js file.

It's much better to handle such things in one language file.
Not with individual configuration.

Add an Image Properties section to the image manager dialog, similar to the one in RadEditor for ASP.NET AJAX: http://demos.telerik.com/aspnet-ajax/editor/examples/xhtmlvalidatortrackchangesformatcodeblockdialogs/defaultcs.aspx

Please add a close event to the ActionSheet.  This could be used in conjunction with the open event to allow the user to use the back button on Android to close the ActionSheet.

is the kendo ui supported in tablet?

Almost all data drive UI needs a simple pagination control.  I've seen other requests ask for other controls to have pagination (like grids) but I just want a properly styled pagination control that could be used to either control another UI control (grid, table, etc) or simply just be hyperlinks.  

I would really like to see a Gauge control similar to what is available through the Telerik Silverlight controls.

It would be awesome if you added masking to input fields, similar to what you've done with validation. Many times I need to add formatting to the display of a field that and I don't want to store the extra characters associated with the on screen formatting. Formatting for telephone numbers, email addresses, currency are the ones immediately useful. Although other libraries exist for these, it would be nice to consolidate them into a single library!

I'd like to use Kendo, but the available themes are too restrictive, much less vibrant that the MVC themes.  And the Themebuilder is not adequate to extend or alter them.  Can you add richer themes to Kendo?