I have had the iPhone since 1Gen I honestly believe it is time to move to Samsung Galaxy Note 3, with the watch, they are just starting to offer more of what I want to see..
You'll regret it and switch back within three months. Trust me on this, I did it last year when Apple release a longer 4S and called it iPhone 5. I bought a Galaxy and hated it.
Android is awful. It's gimmicky, yet the gimmicks are clunky and do not work as advertised. Google Play is tedious and cumbersome. Losing iCloud and the seamless integration between devices was like losing a limb.
Hardware-wise, nothing stood out about the Samsung. The faster (at the time) processor gave a negligible performance boost. The screen was bigger, but didn't hold a candle to the Retina display. I had to zoom webpages in to read them, which pretty much negated the reason for having a larger screen in the first place.
But by all means, don't take my word for it. Make the switch.
But don't say you weren't warned.