Nokia's Lumia 820 was firmly stuck in the Lumia 920's shadow -- in fact it barely figured in Nokia's big presentation. But one thing it holds over its bigger, publicity-hungry brother is the ability to switch covers, so while the 820 won't get its wireless charging built-in, a specific case can add the same functionality. Well, we knew that already, but Nokia's now revealed the phone's own range of dedicated ruggedized cases. These covers, arriving in green, yellow and orange, will measure in at the same length and width as the others, but will protrude marginally more, offering some protection to that 4.3-inch screen when it comes into contact with surfaces. A "rubber-like" trim will afford some extra protection to those glossy corners too. Expect the toughened cases to appear alongside the Lumia 820 at launch -- whenever that is.