I've tested both out and I choose the 5S. Both are amazing phones with the best software. It really all just comes down to personal preference. For me, I like how fluid iOS is and how seamlessly everything works together with an iPhone. Between that and the premium feel of the phone itself, I put it in first place. I feel that Samsung just takes every little neat thing and throws it at the GS4. iPhone is about design, organization, and thought behind how things work. The GS4 is about boasting the best specs and having the most features, options, and customization.
