It is expected when RenderMode is set to Auto the grid to have different rendering on desktop and when you view it on mobile device. This is the reason built-in Adaptive behavior to be provided for the control.
When you change the grid RenderMode
a context menu placed at the top right corner of the grid will appear for mobile device.By clicking on it you can reduce the columns number on the client or rearrange them in the desired order.
Also when you set EnableHeaderContextMenu and EnableHeaderContextFilterMenu properties to true a Column Settings menu placed inside each column header will be shown. Via the Column Settings popup which will open you can group the respective column, sort and filter its data.
For more information about grid adaptive behavior you can refer to the article below:
You can also test the grid behavior on mobile device in this demo:
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