Cases which have lips and are minimal and don't have big lines or logos or branding
This was already previously mentioned, but the black leather Apple case fits a lot of your credentials.
- It has lips that curve to the phone great, and the camera slot raises just enough to protect the raised lens.
- It's extraordinarily minimal (I'm not sure how much more minimal you can get when it comes to size/thickness, really).
- No lines or markings of any kind, save for the imprinted Apple logo on the back of the case. While the logo is there, it really doesn't stand out much at all. It's not very noticeable, and it blends with the case well.
- Very easy to slide on and off, without compromising phone security.
- Another tidbit about the leather case (which I haven't seen mentioned around here much) is that its interior is lined with felt, which I really enjoy. Adds cushion and security, and when a stray grain of sand gets in there, the felt does its job.
If you have the $45 to spend on a case, I highly recommend it. It feels very nice in the hand, and it feels very durable and long-lasting.