I hate using a case but I always use one. On top of the fact that I'm clumsy (my wife will vouch for that) I have two kids that love running around the house with Daddy's iPhone. A case is a must for me!
For those who dislike cases but want protection while carrying, I suggest a leather slip-in pouch. This style of case was always popular with BlackBerry users, me included.
This is exactly what I was going to say. I'm still on a Z30, deciding between either a Priv or 6S Plus (waiting for Verizon's Priv) and all I've ever used is a leather pouch. It's protected the entire time I'm not using it, including from being scratched in a pocket or when I toss it on the table, but I don't have to have any more bulk when I use it.
Apple puts so much effort into the design and materials of their phones I think it's a shame that everyone just covers it up in a $20 case.
I prefer naked. I have a ZAGG shield on the back of my iPhone and ZAGG Glass screen on the front. I keep my iPhone in a super slim SENA leather pouch when in my pocket.
I tried the leather pouch but found the leather too flimsy because it's so thin. Do you have to really work it to get it back IN to the pouch (I found I did so I returned it).
I prefer naked but hate scratches. I have an Otterbox Defender with a ZAGG screen protector but would prefer a clear case. Any recommendations?