Looks like one of your custom icon styles is affecting the application rendering. The thing is that Kendo UI Mobile is adding a .km-phone CSS class to the application root (html tag). You on the other hand have a custom icon named phone which as rest of our icons appends km- to its name and uses it as a class name. This however places the mask image on the root too. To avoid this, change your icon name to something else or remove the style altogether (I didn't see you using it anywhere). We on the other hand will see if we can change something to avoid such issues in the future.
the Telerik team
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