Slightly different opinion than Snn5, no disrespect intended.
TUDIA Ultra-Slim Melody Series TPU case.
Very low profile. Adds just the right amount of grip, without being bulky. Probably would not protect the phone much from a drop, but this will prevent it leaving your hands.
Otterbox also allows wireless charging. I have also tried a few off eBay that were dual layer hybrids. I stick to the OB because of warranty and it just works for me. The others as above or the TPUs offer flexibility if you like to change your case a lot.