A DataStorage that can be used for both in Windows 8.1 and Windows Phone 8.1 apps.

ListView: Expose setter for SelectedItem property and implement it, so that setting this property applies the corresponding style to the selected item.

Declined: The SelectedItem property has public setter. Setting it makes the style be applied as expected on the item.

Declined: Currently UWP does not have an ImageEditor control. On the following link you can find a feature request where you can vote for introducing such a control and track its status: https://feedback.telerik.com/Project/167/Feedback/Details/201118-new-control-image-editor-port-to-uwp

After multiple control reload the memory is not released.

Declined: Currently UWP does not have an ImageEditor control. On the following link you can find a feature request where you can vote for introducing such a control and track its status: https://feedback.telerik.com/Project/167/Feedback/Details/201118-new-control-image-editor-port-to-uwp

Port RadGauge to Windows Universal

Universal Window component.

Universal rich text editor.

A control that is able to display PDF files natively in Universal App 

Port Image editor from Win 8.1 supporting different form factors.

The one that's already in win8 phone and UI for WPF. 
Please please

Port the Windows Phone ImageEditor to WinRT.

http://www.telerik.com/products/windows-phone/overview/all-controls/image-editor.aspx

A control that is able to display PDF files natively in Universal App

Allow UWP to use Gantt charts similar if not better than the ones used in WPF