For an affordable device the Lumia 535 has some rather nifty accessories.
Lumia Blog UK have posted this video looking at the official Lumia 535 flip shell (CC-3092).
The shell replaces the battery cover, and then offers an integrated flip cover (not active) lined with microfibre, to not only protect but keep your screen clean.
It also offers a slot for your credit card, making it even more useful.
The cover ranges between £13.99 and £17.99 on Amazon.co.uk. Pick it up here.