In my search for a leather wallet case for my iPhone 6 Plus I found this one to be one of the best available. It’s made of leather, unlike many others that are “leather-like”, and has worked very well over the few weeks of use. The phone snaps into a plastic shell and the pockets hold a half dozen cards. There’s a pocket for holding a few bills or receipts, as well. At $27.99 it’s a bargain.
I would also recommend adding a protective screen saver whenever cards come in contact with the display to protect the coatings from abrading. Something such as this. When I ordered it from Amazon on a Saturday morning, it was delivered at 8:30pm the same evening.