I got a s4 and it's pretty bada*s. I'm not a techie in the slighest, but some of the features this phone has is unbelievable. Don't know much about apple but my cousin went from the iphone s5 (or s6...?) - the latest model - to the s4. He says it's better. Doesn't quite answer your question. I could never buy apple phones..it's too small.
mainly the quality of the interface