Don't know the logical thinking behind putting cover on phones. If there is some kind of battery pack in there, then may be.
But putting a ugly bulky case on a beautifully designed mobile is crazy.
Companies like Apple put so much effort into making their phones sleeker and stylish, then you go and put a cheap ugly case on it and ruin it.
Apple uses gorilla glass and aluminium to make sure normal scratches don't affect the phone. So why put an ugly case and ruin such a beautiful design.
If you take care of your phone reasonable it should look pretty and last quite a bit without a case.
The moment you put case you are also bound to neglect the phone thinking the case will protect it.
Would you buy a Ferrari and wrap it in a cover?
So stop worrying and start enjoying using your beautiful, slim mobile that you paid so much money for.
So no more cases please...