This is the way it works, you cannot sell anything that is branded in the same way as the brand name.
If it looks SIMILAR (not identical) and has no branding, it is considered a clone.
ou can sell clones legally anywhere, you just ave to make sure you do not say it is an Iphone (or whatever the brand you are dealing with).
Think of it this way, when you go into a cell phone store to get a charger, you can buy the Samsung one, or another one that will work with Samsung, but is made by Taeku-Yammioto.
Replicas are illegal because they have branding that is illegal for you to use without permission from the brand manufacturer.
Clones are legal, because they have no branding, and you have permission to sell them from the clone manufacturer.
if you sell your product as an Iphone case, it is illegal. If you sell them as Iphone compatible cases, you are clear.
Those two links appear to show that Apple are suing people/companies for allegedly selling fake Apple products or products that are using the Apple logo or name to sell.
I am not sure if they have a case if for example you listed a wall charger that could recharge an Ipad or other Apple product, you can buy universal chargers in shops and online which are capable of recharging numerous different items and yet there is no complaint about that.
The trouble with the likes of Apple is they have gotten so big they can afford to bully everyone, the outright fakes I can understand but other companies producing generic items that can also be used with Apple products should be allowed as long as they aren't trading on the Apple name, but that is in an ideal world I suppose.
I am referring to the links from bigcasey123