Do I iphone 5s s break easier?

Does the screen crack easier? Even with a case?

No they are all the same made of the same glass material so it brakes the same as any of the others

If you have a protective case on the phone it shouldn't break. It all depends on how hard you drop the phone. Keep in mind that iphones are made of glass so they shouldn't be dropped. I've had my iphone 4S for 1 year, 8 months, 25 days and it's taken hits to the cement LOTS of time before, many times without a case or with an unprotected case on. It still works and looks brand new. Only thing that really freaked me out was a day ago I dropped the phone on tile floor at school and the screen went completely blue for a couple seconds but eventually turned off and back on and still works perfectly fine. I was pretty sure I cracked the screen when it ended up going screen first. I picked it up to see it still looking like it just came out of the box it came in. My aunt and my friend have the iphone 5S and my aunt has 2 kids that play on her phone All the time throwing it around and stuff yet still works perfectly fine and looks brand new. My friend also has a younger sister that uses it all the time and throws it around also. Still looks like it came straight out of the box. The best case they both recommend is getting an otterbox.

All the iPhones are pretty easy to crack. But having a case does help to reduce the effect and make it less likely to break that easily. Also, you should get a screen protector too.

5S is aluminum so its way stronger then other phones, as far as the glass front if you drop it face down on cement then yeah I would expect damage as I would anything you drop on cement like that, don't drop it and keep it in your pocket.